Commit | Line | Data |
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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); | |
d97e63b6 | 40 | |
df24a2b9 | 41 | struct btrfs_path *btrfs_alloc_path(void) |
2c90e5d6 | 42 | { |
df24a2b9 | 43 | struct btrfs_path *path; |
e00f7308 JM |
44 | path = kmem_cache_zalloc(btrfs_path_cachep, GFP_NOFS); |
45 | if (path) | |
2cc58cf2 | 46 | path->reada = 1; |
df24a2b9 | 47 | return path; |
2c90e5d6 CM |
48 | } |
49 | ||
b4ce94de CM |
50 | /* |
51 | * set all locked nodes in the path to blocking locks. This should | |
52 | * be done before scheduling | |
53 | */ | |
54 | noinline void btrfs_set_path_blocking(struct btrfs_path *p) | |
55 | { | |
56 | int i; | |
57 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { | |
58 | if (p->nodes[i] && p->locks[i]) | |
59 | btrfs_set_lock_blocking(p->nodes[i]); | |
60 | } | |
61 | } | |
62 | ||
63 | /* | |
64 | * reset all the locked nodes in the patch to spinning locks. | |
4008c04a CM |
65 | * |
66 | * held is used to keep lockdep happy, when lockdep is enabled | |
67 | * we set held to a blocking lock before we go around and | |
68 | * retake all the spinlocks in the path. You can safely use NULL | |
69 | * for held | |
b4ce94de | 70 | */ |
4008c04a CM |
71 | noinline void btrfs_clear_path_blocking(struct btrfs_path *p, |
72 | struct extent_buffer *held) | |
b4ce94de CM |
73 | { |
74 | int i; | |
4008c04a CM |
75 | |
76 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
77 | /* lockdep really cares that we take all of these spinlocks | |
78 | * in the right order. If any of the locks in the path are not | |
79 | * currently blocking, it is going to complain. So, make really | |
80 | * really sure by forcing the path to blocking before we clear | |
81 | * the path blocking. | |
82 | */ | |
83 | if (held) | |
84 | btrfs_set_lock_blocking(held); | |
85 | btrfs_set_path_blocking(p); | |
86 | #endif | |
87 | ||
88 | for (i = BTRFS_MAX_LEVEL - 1; i >= 0; i--) { | |
b4ce94de CM |
89 | if (p->nodes[i] && p->locks[i]) |
90 | btrfs_clear_lock_blocking(p->nodes[i]); | |
91 | } | |
4008c04a CM |
92 | |
93 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
94 | if (held) | |
95 | btrfs_clear_lock_blocking(held); | |
96 | #endif | |
b4ce94de CM |
97 | } |
98 | ||
d352ac68 | 99 | /* this also releases the path */ |
df24a2b9 | 100 | void btrfs_free_path(struct btrfs_path *p) |
be0e5c09 | 101 | { |
df24a2b9 CM |
102 | btrfs_release_path(NULL, p); |
103 | kmem_cache_free(btrfs_path_cachep, p); | |
be0e5c09 CM |
104 | } |
105 | ||
d352ac68 CM |
106 | /* |
107 | * path release drops references on the extent buffers in the path | |
108 | * and it drops any locks held by this path | |
109 | * | |
110 | * It is safe to call this on paths that no locks or extent buffers held. | |
111 | */ | |
d397712b | 112 | noinline void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p) |
eb60ceac CM |
113 | { |
114 | int i; | |
a2135011 | 115 | |
234b63a0 | 116 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
3f157a2f | 117 | p->slots[i] = 0; |
eb60ceac | 118 | if (!p->nodes[i]) |
925baedd CM |
119 | continue; |
120 | if (p->locks[i]) { | |
121 | btrfs_tree_unlock(p->nodes[i]); | |
122 | p->locks[i] = 0; | |
123 | } | |
5f39d397 | 124 | free_extent_buffer(p->nodes[i]); |
3f157a2f | 125 | p->nodes[i] = NULL; |
eb60ceac CM |
126 | } |
127 | } | |
128 | ||
d352ac68 CM |
129 | /* |
130 | * safely gets a reference on the root node of a tree. A lock | |
131 | * is not taken, so a concurrent writer may put a different node | |
132 | * at the root of the tree. See btrfs_lock_root_node for the | |
133 | * looping required. | |
134 | * | |
135 | * The extent buffer returned by this has a reference taken, so | |
136 | * it won't disappear. It may stop being the root of the tree | |
137 | * at any time because there are no locks held. | |
138 | */ | |
925baedd CM |
139 | struct extent_buffer *btrfs_root_node(struct btrfs_root *root) |
140 | { | |
141 | struct extent_buffer *eb; | |
142 | spin_lock(&root->node_lock); | |
143 | eb = root->node; | |
144 | extent_buffer_get(eb); | |
145 | spin_unlock(&root->node_lock); | |
146 | return eb; | |
147 | } | |
148 | ||
d352ac68 CM |
149 | /* loop around taking references on and locking the root node of the |
150 | * tree until you end up with a lock on the root. A locked buffer | |
151 | * is returned, with a reference held. | |
152 | */ | |
925baedd CM |
153 | struct extent_buffer *btrfs_lock_root_node(struct btrfs_root *root) |
154 | { | |
155 | struct extent_buffer *eb; | |
156 | ||
d397712b | 157 | while (1) { |
925baedd CM |
158 | eb = btrfs_root_node(root); |
159 | btrfs_tree_lock(eb); | |
160 | ||
161 | spin_lock(&root->node_lock); | |
162 | if (eb == root->node) { | |
163 | spin_unlock(&root->node_lock); | |
164 | break; | |
165 | } | |
166 | spin_unlock(&root->node_lock); | |
167 | ||
168 | btrfs_tree_unlock(eb); | |
169 | free_extent_buffer(eb); | |
170 | } | |
171 | return eb; | |
172 | } | |
173 | ||
d352ac68 CM |
174 | /* cowonly root (everything not a reference counted cow subvolume), just get |
175 | * put onto a simple dirty list. transaction.c walks this to make sure they | |
176 | * get properly updated on disk. | |
177 | */ | |
0b86a832 CM |
178 | static void add_root_to_dirty_list(struct btrfs_root *root) |
179 | { | |
180 | if (root->track_dirty && list_empty(&root->dirty_list)) { | |
181 | list_add(&root->dirty_list, | |
182 | &root->fs_info->dirty_cowonly_roots); | |
183 | } | |
184 | } | |
185 | ||
d352ac68 CM |
186 | /* |
187 | * used by snapshot creation to make a copy of a root for a tree with | |
188 | * a given objectid. The buffer with the new root node is returned in | |
189 | * cow_ret, and this func returns zero on success or a negative error code. | |
190 | */ | |
be20aa9d CM |
191 | int btrfs_copy_root(struct btrfs_trans_handle *trans, |
192 | struct btrfs_root *root, | |
193 | struct extent_buffer *buf, | |
194 | struct extent_buffer **cow_ret, u64 new_root_objectid) | |
195 | { | |
196 | struct extent_buffer *cow; | |
197 | u32 nritems; | |
198 | int ret = 0; | |
199 | int level; | |
4aec2b52 | 200 | struct btrfs_root *new_root; |
be20aa9d | 201 | |
4aec2b52 CM |
202 | new_root = kmalloc(sizeof(*new_root), GFP_NOFS); |
203 | if (!new_root) | |
204 | return -ENOMEM; | |
205 | ||
206 | memcpy(new_root, root, sizeof(*new_root)); | |
207 | new_root->root_key.objectid = new_root_objectid; | |
be20aa9d CM |
208 | |
209 | WARN_ON(root->ref_cows && trans->transid != | |
210 | root->fs_info->running_transaction->transid); | |
211 | WARN_ON(root->ref_cows && trans->transid != root->last_trans); | |
212 | ||
213 | level = btrfs_header_level(buf); | |
214 | nritems = btrfs_header_nritems(buf); | |
31840ae1 ZY |
215 | |
216 | cow = btrfs_alloc_free_block(trans, new_root, buf->len, 0, | |
217 | new_root_objectid, trans->transid, | |
218 | level, buf->start, 0); | |
4aec2b52 CM |
219 | if (IS_ERR(cow)) { |
220 | kfree(new_root); | |
be20aa9d | 221 | return PTR_ERR(cow); |
4aec2b52 | 222 | } |
be20aa9d CM |
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); | |
227 | btrfs_set_header_owner(cow, new_root_objectid); | |
63b10fc4 | 228 | btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN); |
be20aa9d | 229 | |
2b82032c YZ |
230 | write_extent_buffer(cow, root->fs_info->fsid, |
231 | (unsigned long)btrfs_header_fsid(cow), | |
232 | BTRFS_FSID_SIZE); | |
233 | ||
be20aa9d | 234 | WARN_ON(btrfs_header_generation(buf) > trans->transid); |
31840ae1 | 235 | ret = btrfs_inc_ref(trans, new_root, buf, cow, NULL); |
4aec2b52 CM |
236 | kfree(new_root); |
237 | ||
be20aa9d CM |
238 | if (ret) |
239 | return ret; | |
240 | ||
241 | btrfs_mark_buffer_dirty(cow); | |
242 | *cow_ret = cow; | |
243 | return 0; | |
244 | } | |
245 | ||
d352ac68 | 246 | /* |
d397712b CM |
247 | * does the dirty work in cow of a single block. The parent block (if |
248 | * supplied) is updated to point to the new cow copy. The new buffer is marked | |
249 | * dirty and returned locked. If you modify the block it needs to be marked | |
250 | * dirty again. | |
d352ac68 CM |
251 | * |
252 | * search_start -- an allocation hint for the new block | |
253 | * | |
d397712b CM |
254 | * empty_size -- a hint that you plan on doing more cow. This is the size in |
255 | * bytes the allocator should try to find free next to the block it returns. | |
256 | * This is just a hint and may be ignored by the allocator. | |
d352ac68 | 257 | */ |
d397712b | 258 | static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, |
5f39d397 CM |
259 | struct btrfs_root *root, |
260 | struct extent_buffer *buf, | |
261 | struct extent_buffer *parent, int parent_slot, | |
262 | struct extent_buffer **cow_ret, | |
9fa8cfe7 | 263 | u64 search_start, u64 empty_size) |
02217ed2 | 264 | { |
31840ae1 | 265 | u64 parent_start; |
5f39d397 | 266 | struct extent_buffer *cow; |
7bb86316 | 267 | u32 nritems; |
6702ed49 | 268 | int ret = 0; |
7bb86316 | 269 | int level; |
925baedd | 270 | int unlock_orig = 0; |
7bb86316 | 271 | |
925baedd CM |
272 | if (*cow_ret == buf) |
273 | unlock_orig = 1; | |
274 | ||
b9447ef8 | 275 | btrfs_assert_tree_locked(buf); |
925baedd | 276 | |
31840ae1 ZY |
277 | if (parent) |
278 | parent_start = parent->start; | |
279 | else | |
280 | parent_start = 0; | |
281 | ||
7bb86316 CM |
282 | WARN_ON(root->ref_cows && trans->transid != |
283 | root->fs_info->running_transaction->transid); | |
6702ed49 | 284 | WARN_ON(root->ref_cows && trans->transid != root->last_trans); |
5f39d397 | 285 | |
7bb86316 CM |
286 | level = btrfs_header_level(buf); |
287 | nritems = btrfs_header_nritems(buf); | |
31840ae1 | 288 | |
9fa8cfe7 CM |
289 | cow = btrfs_alloc_free_block(trans, root, buf->len, |
290 | parent_start, root->root_key.objectid, | |
291 | trans->transid, level, | |
292 | search_start, empty_size); | |
54aa1f4d CM |
293 | if (IS_ERR(cow)) |
294 | return PTR_ERR(cow); | |
6702ed49 | 295 | |
b4ce94de CM |
296 | /* cow is set to blocking by btrfs_init_new_buffer */ |
297 | ||
5f39d397 | 298 | copy_extent_buffer(cow, buf, 0, 0, cow->len); |
db94535d | 299 | btrfs_set_header_bytenr(cow, cow->start); |
5f39d397 CM |
300 | btrfs_set_header_generation(cow, trans->transid); |
301 | btrfs_set_header_owner(cow, root->root_key.objectid); | |
63b10fc4 | 302 | btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN); |
6702ed49 | 303 | |
2b82032c YZ |
304 | write_extent_buffer(cow, root->fs_info->fsid, |
305 | (unsigned long)btrfs_header_fsid(cow), | |
306 | BTRFS_FSID_SIZE); | |
307 | ||
5f39d397 CM |
308 | WARN_ON(btrfs_header_generation(buf) > trans->transid); |
309 | if (btrfs_header_generation(buf) != trans->transid) { | |
31840ae1 | 310 | u32 nr_extents; |
31840ae1 | 311 | ret = btrfs_inc_ref(trans, root, buf, cow, &nr_extents); |
6702ed49 CM |
312 | if (ret) |
313 | return ret; | |
31840ae1 ZY |
314 | |
315 | ret = btrfs_cache_ref(trans, root, buf, nr_extents); | |
316 | WARN_ON(ret); | |
1a40e23b ZY |
317 | } else if (btrfs_header_owner(buf) == BTRFS_TREE_RELOC_OBJECTID) { |
318 | /* | |
319 | * There are only two places that can drop reference to | |
320 | * tree blocks owned by living reloc trees, one is here, | |
f82d02d9 | 321 | * the other place is btrfs_drop_subtree. In both places, |
1a40e23b ZY |
322 | * we check reference count while tree block is locked. |
323 | * Furthermore, if reference count is one, it won't get | |
324 | * increased by someone else. | |
325 | */ | |
326 | u32 refs; | |
327 | ret = btrfs_lookup_extent_ref(trans, root, buf->start, | |
328 | buf->len, &refs); | |
329 | BUG_ON(ret); | |
330 | if (refs == 1) { | |
331 | ret = btrfs_update_ref(trans, root, buf, cow, | |
332 | 0, nritems); | |
333 | clean_tree_block(trans, root, buf); | |
334 | } else { | |
335 | ret = btrfs_inc_ref(trans, root, buf, cow, NULL); | |
336 | } | |
337 | BUG_ON(ret); | |
6702ed49 | 338 | } else { |
31840ae1 ZY |
339 | ret = btrfs_update_ref(trans, root, buf, cow, 0, nritems); |
340 | if (ret) | |
341 | return ret; | |
6702ed49 CM |
342 | clean_tree_block(trans, root, buf); |
343 | } | |
344 | ||
1a40e23b | 345 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { |
1a40e23b ZY |
346 | ret = btrfs_reloc_tree_cache_ref(trans, root, cow, buf->start); |
347 | WARN_ON(ret); | |
348 | } | |
349 | ||
02217ed2 | 350 | if (buf == root->node) { |
925baedd | 351 | WARN_ON(parent && parent != buf); |
925baedd CM |
352 | |
353 | spin_lock(&root->node_lock); | |
02217ed2 | 354 | root->node = cow; |
5f39d397 | 355 | extent_buffer_get(cow); |
925baedd CM |
356 | spin_unlock(&root->node_lock); |
357 | ||
2c90e5d6 | 358 | if (buf != root->commit_root) { |
db94535d | 359 | btrfs_free_extent(trans, root, buf->start, |
31840ae1 ZY |
360 | buf->len, buf->start, |
361 | root->root_key.objectid, | |
362 | btrfs_header_generation(buf), | |
3bb1a1bc | 363 | level, 1); |
2c90e5d6 | 364 | } |
5f39d397 | 365 | free_extent_buffer(buf); |
0b86a832 | 366 | add_root_to_dirty_list(root); |
02217ed2 | 367 | } else { |
5f39d397 | 368 | btrfs_set_node_blockptr(parent, parent_slot, |
db94535d | 369 | cow->start); |
74493f7a CM |
370 | WARN_ON(trans->transid == 0); |
371 | btrfs_set_node_ptr_generation(parent, parent_slot, | |
372 | trans->transid); | |
d6025579 | 373 | btrfs_mark_buffer_dirty(parent); |
5f39d397 | 374 | WARN_ON(btrfs_header_generation(parent) != trans->transid); |
7bb86316 | 375 | btrfs_free_extent(trans, root, buf->start, buf->len, |
31840ae1 | 376 | parent_start, btrfs_header_owner(parent), |
3bb1a1bc | 377 | btrfs_header_generation(parent), level, 1); |
02217ed2 | 378 | } |
925baedd CM |
379 | if (unlock_orig) |
380 | btrfs_tree_unlock(buf); | |
5f39d397 | 381 | free_extent_buffer(buf); |
ccd467d6 | 382 | btrfs_mark_buffer_dirty(cow); |
2c90e5d6 | 383 | *cow_ret = cow; |
02217ed2 CM |
384 | return 0; |
385 | } | |
386 | ||
d352ac68 CM |
387 | /* |
388 | * cows a single block, see __btrfs_cow_block for the real work. | |
389 | * This version of it has extra checks so that a block isn't cow'd more than | |
390 | * once per transaction, as long as it hasn't been written yet | |
391 | */ | |
d397712b | 392 | noinline int btrfs_cow_block(struct btrfs_trans_handle *trans, |
5f39d397 CM |
393 | struct btrfs_root *root, struct extent_buffer *buf, |
394 | struct extent_buffer *parent, int parent_slot, | |
9fa8cfe7 | 395 | struct extent_buffer **cow_ret) |
6702ed49 CM |
396 | { |
397 | u64 search_start; | |
f510cfec | 398 | int ret; |
dc17ff8f | 399 | |
6702ed49 | 400 | if (trans->transaction != root->fs_info->running_transaction) { |
d397712b CM |
401 | printk(KERN_CRIT "trans %llu running %llu\n", |
402 | (unsigned long long)trans->transid, | |
403 | (unsigned long long) | |
6702ed49 CM |
404 | root->fs_info->running_transaction->transid); |
405 | WARN_ON(1); | |
406 | } | |
407 | if (trans->transid != root->fs_info->generation) { | |
d397712b CM |
408 | printk(KERN_CRIT "trans %llu running %llu\n", |
409 | (unsigned long long)trans->transid, | |
410 | (unsigned long long)root->fs_info->generation); | |
6702ed49 CM |
411 | WARN_ON(1); |
412 | } | |
dc17ff8f | 413 | |
5b21f2ed ZY |
414 | if (btrfs_header_generation(buf) == trans->transid && |
415 | btrfs_header_owner(buf) == root->root_key.objectid && | |
63b10fc4 | 416 | !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) { |
6702ed49 CM |
417 | *cow_ret = buf; |
418 | return 0; | |
419 | } | |
c487685d | 420 | |
0b86a832 | 421 | search_start = buf->start & ~((u64)(1024 * 1024 * 1024) - 1); |
b4ce94de CM |
422 | |
423 | if (parent) | |
424 | btrfs_set_lock_blocking(parent); | |
425 | btrfs_set_lock_blocking(buf); | |
426 | ||
f510cfec | 427 | ret = __btrfs_cow_block(trans, root, buf, parent, |
9fa8cfe7 | 428 | parent_slot, cow_ret, search_start, 0); |
f510cfec | 429 | return ret; |
6702ed49 CM |
430 | } |
431 | ||
d352ac68 CM |
432 | /* |
433 | * helper function for defrag to decide if two blocks pointed to by a | |
434 | * node are actually close by | |
435 | */ | |
6b80053d | 436 | static int close_blocks(u64 blocknr, u64 other, u32 blocksize) |
6702ed49 | 437 | { |
6b80053d | 438 | if (blocknr < other && other - (blocknr + blocksize) < 32768) |
6702ed49 | 439 | return 1; |
6b80053d | 440 | if (blocknr > other && blocknr - (other + blocksize) < 32768) |
6702ed49 CM |
441 | return 1; |
442 | return 0; | |
443 | } | |
444 | ||
081e9573 CM |
445 | /* |
446 | * compare two keys in a memcmp fashion | |
447 | */ | |
448 | static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2) | |
449 | { | |
450 | struct btrfs_key k1; | |
451 | ||
452 | btrfs_disk_key_to_cpu(&k1, disk); | |
453 | ||
454 | if (k1.objectid > k2->objectid) | |
455 | return 1; | |
456 | if (k1.objectid < k2->objectid) | |
457 | return -1; | |
458 | if (k1.type > k2->type) | |
459 | return 1; | |
460 | if (k1.type < k2->type) | |
461 | return -1; | |
462 | if (k1.offset > k2->offset) | |
463 | return 1; | |
464 | if (k1.offset < k2->offset) | |
465 | return -1; | |
466 | return 0; | |
467 | } | |
468 | ||
f3465ca4 JB |
469 | /* |
470 | * same as comp_keys only with two btrfs_key's | |
471 | */ | |
472 | static int comp_cpu_keys(struct btrfs_key *k1, struct btrfs_key *k2) | |
473 | { | |
474 | if (k1->objectid > k2->objectid) | |
475 | return 1; | |
476 | if (k1->objectid < k2->objectid) | |
477 | return -1; | |
478 | if (k1->type > k2->type) | |
479 | return 1; | |
480 | if (k1->type < k2->type) | |
481 | return -1; | |
482 | if (k1->offset > k2->offset) | |
483 | return 1; | |
484 | if (k1->offset < k2->offset) | |
485 | return -1; | |
486 | return 0; | |
487 | } | |
081e9573 | 488 | |
d352ac68 CM |
489 | /* |
490 | * this is used by the defrag code to go through all the | |
491 | * leaves pointed to by a node and reallocate them so that | |
492 | * disk order is close to key order | |
493 | */ | |
6702ed49 | 494 | int btrfs_realloc_node(struct btrfs_trans_handle *trans, |
5f39d397 | 495 | struct btrfs_root *root, struct extent_buffer *parent, |
a6b6e75e CM |
496 | int start_slot, int cache_only, u64 *last_ret, |
497 | struct btrfs_key *progress) | |
6702ed49 | 498 | { |
6b80053d | 499 | struct extent_buffer *cur; |
6702ed49 | 500 | u64 blocknr; |
ca7a79ad | 501 | u64 gen; |
e9d0b13b CM |
502 | u64 search_start = *last_ret; |
503 | u64 last_block = 0; | |
6702ed49 CM |
504 | u64 other; |
505 | u32 parent_nritems; | |
6702ed49 CM |
506 | int end_slot; |
507 | int i; | |
508 | int err = 0; | |
f2183bde | 509 | int parent_level; |
6b80053d CM |
510 | int uptodate; |
511 | u32 blocksize; | |
081e9573 CM |
512 | int progress_passed = 0; |
513 | struct btrfs_disk_key disk_key; | |
6702ed49 | 514 | |
5708b959 CM |
515 | parent_level = btrfs_header_level(parent); |
516 | if (cache_only && parent_level != 1) | |
517 | return 0; | |
518 | ||
d397712b | 519 | if (trans->transaction != root->fs_info->running_transaction) |
6702ed49 | 520 | WARN_ON(1); |
d397712b | 521 | if (trans->transid != root->fs_info->generation) |
6702ed49 | 522 | WARN_ON(1); |
86479a04 | 523 | |
6b80053d | 524 | parent_nritems = btrfs_header_nritems(parent); |
6b80053d | 525 | blocksize = btrfs_level_size(root, parent_level - 1); |
6702ed49 CM |
526 | end_slot = parent_nritems; |
527 | ||
528 | if (parent_nritems == 1) | |
529 | return 0; | |
530 | ||
b4ce94de CM |
531 | btrfs_set_lock_blocking(parent); |
532 | ||
6702ed49 CM |
533 | for (i = start_slot; i < end_slot; i++) { |
534 | int close = 1; | |
a6b6e75e | 535 | |
5708b959 CM |
536 | if (!parent->map_token) { |
537 | map_extent_buffer(parent, | |
538 | btrfs_node_key_ptr_offset(i), | |
539 | sizeof(struct btrfs_key_ptr), | |
540 | &parent->map_token, &parent->kaddr, | |
541 | &parent->map_start, &parent->map_len, | |
542 | KM_USER1); | |
543 | } | |
081e9573 CM |
544 | btrfs_node_key(parent, &disk_key, i); |
545 | if (!progress_passed && comp_keys(&disk_key, progress) < 0) | |
546 | continue; | |
547 | ||
548 | progress_passed = 1; | |
6b80053d | 549 | blocknr = btrfs_node_blockptr(parent, i); |
ca7a79ad | 550 | gen = btrfs_node_ptr_generation(parent, i); |
e9d0b13b CM |
551 | if (last_block == 0) |
552 | last_block = blocknr; | |
5708b959 | 553 | |
6702ed49 | 554 | if (i > 0) { |
6b80053d CM |
555 | other = btrfs_node_blockptr(parent, i - 1); |
556 | close = close_blocks(blocknr, other, blocksize); | |
6702ed49 | 557 | } |
0ef3e66b | 558 | if (!close && i < end_slot - 2) { |
6b80053d CM |
559 | other = btrfs_node_blockptr(parent, i + 1); |
560 | close = close_blocks(blocknr, other, blocksize); | |
6702ed49 | 561 | } |
e9d0b13b CM |
562 | if (close) { |
563 | last_block = blocknr; | |
6702ed49 | 564 | continue; |
e9d0b13b | 565 | } |
5708b959 CM |
566 | if (parent->map_token) { |
567 | unmap_extent_buffer(parent, parent->map_token, | |
568 | KM_USER1); | |
569 | parent->map_token = NULL; | |
570 | } | |
6702ed49 | 571 | |
6b80053d CM |
572 | cur = btrfs_find_tree_block(root, blocknr, blocksize); |
573 | if (cur) | |
1259ab75 | 574 | uptodate = btrfs_buffer_uptodate(cur, gen); |
6b80053d CM |
575 | else |
576 | uptodate = 0; | |
5708b959 | 577 | if (!cur || !uptodate) { |
6702ed49 | 578 | if (cache_only) { |
6b80053d | 579 | free_extent_buffer(cur); |
6702ed49 CM |
580 | continue; |
581 | } | |
6b80053d CM |
582 | if (!cur) { |
583 | cur = read_tree_block(root, blocknr, | |
ca7a79ad | 584 | blocksize, gen); |
6b80053d | 585 | } else if (!uptodate) { |
ca7a79ad | 586 | btrfs_read_buffer(cur, gen); |
f2183bde | 587 | } |
6702ed49 | 588 | } |
e9d0b13b | 589 | if (search_start == 0) |
6b80053d | 590 | search_start = last_block; |
e9d0b13b | 591 | |
e7a84565 | 592 | btrfs_tree_lock(cur); |
b4ce94de | 593 | btrfs_set_lock_blocking(cur); |
6b80053d | 594 | err = __btrfs_cow_block(trans, root, cur, parent, i, |
e7a84565 | 595 | &cur, search_start, |
6b80053d | 596 | min(16 * blocksize, |
9fa8cfe7 | 597 | (end_slot - i) * blocksize)); |
252c38f0 | 598 | if (err) { |
e7a84565 | 599 | btrfs_tree_unlock(cur); |
6b80053d | 600 | free_extent_buffer(cur); |
6702ed49 | 601 | break; |
252c38f0 | 602 | } |
e7a84565 CM |
603 | search_start = cur->start; |
604 | last_block = cur->start; | |
f2183bde | 605 | *last_ret = search_start; |
e7a84565 CM |
606 | btrfs_tree_unlock(cur); |
607 | free_extent_buffer(cur); | |
6702ed49 | 608 | } |
5708b959 CM |
609 | if (parent->map_token) { |
610 | unmap_extent_buffer(parent, parent->map_token, | |
611 | KM_USER1); | |
612 | parent->map_token = NULL; | |
613 | } | |
6702ed49 CM |
614 | return err; |
615 | } | |
616 | ||
74123bd7 CM |
617 | /* |
618 | * The leaf data grows from end-to-front in the node. | |
619 | * this returns the address of the start of the last item, | |
620 | * which is the stop of the leaf data stack | |
621 | */ | |
123abc88 | 622 | static inline unsigned int leaf_data_end(struct btrfs_root *root, |
5f39d397 | 623 | struct extent_buffer *leaf) |
be0e5c09 | 624 | { |
5f39d397 | 625 | u32 nr = btrfs_header_nritems(leaf); |
be0e5c09 | 626 | if (nr == 0) |
123abc88 | 627 | return BTRFS_LEAF_DATA_SIZE(root); |
5f39d397 | 628 | return btrfs_item_offset_nr(leaf, nr - 1); |
be0e5c09 CM |
629 | } |
630 | ||
d352ac68 CM |
631 | /* |
632 | * extra debugging checks to make sure all the items in a key are | |
633 | * well formed and in the proper order | |
634 | */ | |
123abc88 CM |
635 | static int check_node(struct btrfs_root *root, struct btrfs_path *path, |
636 | int level) | |
aa5d6bed | 637 | { |
5f39d397 CM |
638 | struct extent_buffer *parent = NULL; |
639 | struct extent_buffer *node = path->nodes[level]; | |
640 | struct btrfs_disk_key parent_key; | |
641 | struct btrfs_disk_key node_key; | |
aa5d6bed | 642 | int parent_slot; |
8d7be552 CM |
643 | int slot; |
644 | struct btrfs_key cpukey; | |
5f39d397 | 645 | u32 nritems = btrfs_header_nritems(node); |
aa5d6bed CM |
646 | |
647 | if (path->nodes[level + 1]) | |
5f39d397 | 648 | parent = path->nodes[level + 1]; |
a1f39630 | 649 | |
8d7be552 | 650 | slot = path->slots[level]; |
7518a238 CM |
651 | BUG_ON(nritems == 0); |
652 | if (parent) { | |
a1f39630 | 653 | parent_slot = path->slots[level + 1]; |
5f39d397 CM |
654 | btrfs_node_key(parent, &parent_key, parent_slot); |
655 | btrfs_node_key(node, &node_key, 0); | |
656 | BUG_ON(memcmp(&parent_key, &node_key, | |
e2fa7227 | 657 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 658 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
db94535d | 659 | btrfs_header_bytenr(node)); |
aa5d6bed | 660 | } |
123abc88 | 661 | BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root)); |
8d7be552 | 662 | if (slot != 0) { |
5f39d397 CM |
663 | btrfs_node_key_to_cpu(node, &cpukey, slot - 1); |
664 | btrfs_node_key(node, &node_key, slot); | |
665 | BUG_ON(comp_keys(&node_key, &cpukey) <= 0); | |
8d7be552 CM |
666 | } |
667 | if (slot < nritems - 1) { | |
5f39d397 CM |
668 | btrfs_node_key_to_cpu(node, &cpukey, slot + 1); |
669 | btrfs_node_key(node, &node_key, slot); | |
670 | BUG_ON(comp_keys(&node_key, &cpukey) >= 0); | |
aa5d6bed CM |
671 | } |
672 | return 0; | |
673 | } | |
674 | ||
d352ac68 CM |
675 | /* |
676 | * extra checking to make sure all the items in a leaf are | |
677 | * well formed and in the proper order | |
678 | */ | |
123abc88 CM |
679 | static int check_leaf(struct btrfs_root *root, struct btrfs_path *path, |
680 | int level) | |
aa5d6bed | 681 | { |
5f39d397 CM |
682 | struct extent_buffer *leaf = path->nodes[level]; |
683 | struct extent_buffer *parent = NULL; | |
aa5d6bed | 684 | int parent_slot; |
8d7be552 | 685 | struct btrfs_key cpukey; |
5f39d397 CM |
686 | struct btrfs_disk_key parent_key; |
687 | struct btrfs_disk_key leaf_key; | |
688 | int slot = path->slots[0]; | |
8d7be552 | 689 | |
5f39d397 | 690 | u32 nritems = btrfs_header_nritems(leaf); |
aa5d6bed CM |
691 | |
692 | if (path->nodes[level + 1]) | |
5f39d397 | 693 | parent = path->nodes[level + 1]; |
7518a238 CM |
694 | |
695 | if (nritems == 0) | |
696 | return 0; | |
697 | ||
698 | if (parent) { | |
a1f39630 | 699 | parent_slot = path->slots[level + 1]; |
5f39d397 CM |
700 | btrfs_node_key(parent, &parent_key, parent_slot); |
701 | btrfs_item_key(leaf, &leaf_key, 0); | |
6702ed49 | 702 | |
5f39d397 | 703 | BUG_ON(memcmp(&parent_key, &leaf_key, |
e2fa7227 | 704 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 705 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
db94535d | 706 | btrfs_header_bytenr(leaf)); |
5f39d397 | 707 | } |
5f39d397 CM |
708 | if (slot != 0 && slot < nritems - 1) { |
709 | btrfs_item_key(leaf, &leaf_key, slot); | |
710 | btrfs_item_key_to_cpu(leaf, &cpukey, slot - 1); | |
711 | if (comp_keys(&leaf_key, &cpukey) <= 0) { | |
712 | btrfs_print_leaf(root, leaf); | |
d397712b | 713 | printk(KERN_CRIT "slot %d offset bad key\n", slot); |
5f39d397 CM |
714 | BUG_ON(1); |
715 | } | |
716 | if (btrfs_item_offset_nr(leaf, slot - 1) != | |
717 | btrfs_item_end_nr(leaf, slot)) { | |
718 | btrfs_print_leaf(root, leaf); | |
d397712b | 719 | printk(KERN_CRIT "slot %d offset bad\n", slot); |
5f39d397 CM |
720 | BUG_ON(1); |
721 | } | |
8d7be552 CM |
722 | } |
723 | if (slot < nritems - 1) { | |
5f39d397 CM |
724 | btrfs_item_key(leaf, &leaf_key, slot); |
725 | btrfs_item_key_to_cpu(leaf, &cpukey, slot + 1); | |
726 | BUG_ON(comp_keys(&leaf_key, &cpukey) >= 0); | |
727 | if (btrfs_item_offset_nr(leaf, slot) != | |
728 | btrfs_item_end_nr(leaf, slot + 1)) { | |
729 | btrfs_print_leaf(root, leaf); | |
d397712b | 730 | printk(KERN_CRIT "slot %d offset bad\n", slot); |
5f39d397 CM |
731 | BUG_ON(1); |
732 | } | |
aa5d6bed | 733 | } |
5f39d397 CM |
734 | BUG_ON(btrfs_item_offset_nr(leaf, 0) + |
735 | btrfs_item_size_nr(leaf, 0) != BTRFS_LEAF_DATA_SIZE(root)); | |
aa5d6bed CM |
736 | return 0; |
737 | } | |
738 | ||
d397712b | 739 | static noinline int check_block(struct btrfs_root *root, |
98ed5174 | 740 | struct btrfs_path *path, int level) |
aa5d6bed | 741 | { |
85d824c4 | 742 | return 0; |
aa5d6bed | 743 | if (level == 0) |
123abc88 CM |
744 | return check_leaf(root, path, level); |
745 | return check_node(root, path, level); | |
aa5d6bed CM |
746 | } |
747 | ||
74123bd7 | 748 | /* |
5f39d397 CM |
749 | * search for key in the extent_buffer. The items start at offset p, |
750 | * and they are item_size apart. There are 'max' items in p. | |
751 | * | |
74123bd7 CM |
752 | * the slot in the array is returned via slot, and it points to |
753 | * the place where you would insert key if it is not found in | |
754 | * the array. | |
755 | * | |
756 | * slot may point to max if the key is bigger than all of the keys | |
757 | */ | |
e02119d5 CM |
758 | static noinline int generic_bin_search(struct extent_buffer *eb, |
759 | unsigned long p, | |
760 | int item_size, struct btrfs_key *key, | |
761 | int max, int *slot) | |
be0e5c09 CM |
762 | { |
763 | int low = 0; | |
764 | int high = max; | |
765 | int mid; | |
766 | int ret; | |
479965d6 | 767 | struct btrfs_disk_key *tmp = NULL; |
5f39d397 CM |
768 | struct btrfs_disk_key unaligned; |
769 | unsigned long offset; | |
770 | char *map_token = NULL; | |
771 | char *kaddr = NULL; | |
772 | unsigned long map_start = 0; | |
773 | unsigned long map_len = 0; | |
479965d6 | 774 | int err; |
be0e5c09 | 775 | |
d397712b | 776 | while (low < high) { |
be0e5c09 | 777 | mid = (low + high) / 2; |
5f39d397 CM |
778 | offset = p + mid * item_size; |
779 | ||
780 | if (!map_token || offset < map_start || | |
781 | (offset + sizeof(struct btrfs_disk_key)) > | |
782 | map_start + map_len) { | |
479965d6 | 783 | if (map_token) { |
5f39d397 | 784 | unmap_extent_buffer(eb, map_token, KM_USER0); |
479965d6 CM |
785 | map_token = NULL; |
786 | } | |
934d375b CM |
787 | |
788 | err = map_private_extent_buffer(eb, offset, | |
479965d6 CM |
789 | sizeof(struct btrfs_disk_key), |
790 | &map_token, &kaddr, | |
791 | &map_start, &map_len, KM_USER0); | |
792 | ||
793 | if (!err) { | |
794 | tmp = (struct btrfs_disk_key *)(kaddr + offset - | |
795 | map_start); | |
796 | } else { | |
797 | read_extent_buffer(eb, &unaligned, | |
798 | offset, sizeof(unaligned)); | |
799 | tmp = &unaligned; | |
800 | } | |
5f39d397 | 801 | |
5f39d397 CM |
802 | } else { |
803 | tmp = (struct btrfs_disk_key *)(kaddr + offset - | |
804 | map_start); | |
805 | } | |
be0e5c09 CM |
806 | ret = comp_keys(tmp, key); |
807 | ||
808 | if (ret < 0) | |
809 | low = mid + 1; | |
810 | else if (ret > 0) | |
811 | high = mid; | |
812 | else { | |
813 | *slot = mid; | |
479965d6 CM |
814 | if (map_token) |
815 | unmap_extent_buffer(eb, map_token, KM_USER0); | |
be0e5c09 CM |
816 | return 0; |
817 | } | |
818 | } | |
819 | *slot = low; | |
5f39d397 CM |
820 | if (map_token) |
821 | unmap_extent_buffer(eb, map_token, KM_USER0); | |
be0e5c09 CM |
822 | return 1; |
823 | } | |
824 | ||
97571fd0 CM |
825 | /* |
826 | * simple bin_search frontend that does the right thing for | |
827 | * leaves vs nodes | |
828 | */ | |
5f39d397 CM |
829 | static int bin_search(struct extent_buffer *eb, struct btrfs_key *key, |
830 | int level, int *slot) | |
be0e5c09 | 831 | { |
5f39d397 CM |
832 | if (level == 0) { |
833 | return generic_bin_search(eb, | |
834 | offsetof(struct btrfs_leaf, items), | |
0783fcfc | 835 | sizeof(struct btrfs_item), |
5f39d397 | 836 | key, btrfs_header_nritems(eb), |
7518a238 | 837 | slot); |
be0e5c09 | 838 | } else { |
5f39d397 CM |
839 | return generic_bin_search(eb, |
840 | offsetof(struct btrfs_node, ptrs), | |
123abc88 | 841 | sizeof(struct btrfs_key_ptr), |
5f39d397 | 842 | key, btrfs_header_nritems(eb), |
7518a238 | 843 | slot); |
be0e5c09 CM |
844 | } |
845 | return -1; | |
846 | } | |
847 | ||
d352ac68 CM |
848 | /* given a node and slot number, this reads the blocks it points to. The |
849 | * extent buffer is returned with a reference taken (but unlocked). | |
850 | * NULL is returned on error. | |
851 | */ | |
e02119d5 | 852 | static noinline struct extent_buffer *read_node_slot(struct btrfs_root *root, |
5f39d397 | 853 | struct extent_buffer *parent, int slot) |
bb803951 | 854 | { |
ca7a79ad | 855 | int level = btrfs_header_level(parent); |
bb803951 CM |
856 | if (slot < 0) |
857 | return NULL; | |
5f39d397 | 858 | if (slot >= btrfs_header_nritems(parent)) |
bb803951 | 859 | return NULL; |
ca7a79ad CM |
860 | |
861 | BUG_ON(level == 0); | |
862 | ||
db94535d | 863 | return read_tree_block(root, btrfs_node_blockptr(parent, slot), |
ca7a79ad CM |
864 | btrfs_level_size(root, level - 1), |
865 | btrfs_node_ptr_generation(parent, slot)); | |
bb803951 CM |
866 | } |
867 | ||
d352ac68 CM |
868 | /* |
869 | * node level balancing, used to make sure nodes are in proper order for | |
870 | * item deletion. We balance from the top down, so we have to make sure | |
871 | * that a deletion won't leave an node completely empty later on. | |
872 | */ | |
e02119d5 | 873 | static noinline int balance_level(struct btrfs_trans_handle *trans, |
98ed5174 CM |
874 | struct btrfs_root *root, |
875 | struct btrfs_path *path, int level) | |
bb803951 | 876 | { |
5f39d397 CM |
877 | struct extent_buffer *right = NULL; |
878 | struct extent_buffer *mid; | |
879 | struct extent_buffer *left = NULL; | |
880 | struct extent_buffer *parent = NULL; | |
bb803951 CM |
881 | int ret = 0; |
882 | int wret; | |
883 | int pslot; | |
bb803951 | 884 | int orig_slot = path->slots[level]; |
54aa1f4d | 885 | int err_on_enospc = 0; |
79f95c82 | 886 | u64 orig_ptr; |
bb803951 CM |
887 | |
888 | if (level == 0) | |
889 | return 0; | |
890 | ||
5f39d397 | 891 | mid = path->nodes[level]; |
b4ce94de | 892 | |
925baedd | 893 | WARN_ON(!path->locks[level]); |
7bb86316 CM |
894 | WARN_ON(btrfs_header_generation(mid) != trans->transid); |
895 | ||
1d4f8a0c | 896 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
79f95c82 | 897 | |
234b63a0 | 898 | if (level < BTRFS_MAX_LEVEL - 1) |
5f39d397 | 899 | parent = path->nodes[level + 1]; |
bb803951 CM |
900 | pslot = path->slots[level + 1]; |
901 | ||
40689478 CM |
902 | /* |
903 | * deal with the case where there is only one pointer in the root | |
904 | * by promoting the node below to a root | |
905 | */ | |
5f39d397 CM |
906 | if (!parent) { |
907 | struct extent_buffer *child; | |
bb803951 | 908 | |
5f39d397 | 909 | if (btrfs_header_nritems(mid) != 1) |
bb803951 CM |
910 | return 0; |
911 | ||
912 | /* promote the child to a root */ | |
5f39d397 | 913 | child = read_node_slot(root, mid, 0); |
7951f3ce | 914 | BUG_ON(!child); |
925baedd | 915 | btrfs_tree_lock(child); |
b4ce94de | 916 | btrfs_set_lock_blocking(child); |
9fa8cfe7 | 917 | ret = btrfs_cow_block(trans, root, child, mid, 0, &child); |
2f375ab9 Y |
918 | BUG_ON(ret); |
919 | ||
925baedd | 920 | spin_lock(&root->node_lock); |
bb803951 | 921 | root->node = child; |
925baedd CM |
922 | spin_unlock(&root->node_lock); |
923 | ||
31840ae1 | 924 | ret = btrfs_update_extent_ref(trans, root, child->start, |
56bec294 | 925 | child->len, |
31840ae1 ZY |
926 | mid->start, child->start, |
927 | root->root_key.objectid, | |
3bb1a1bc | 928 | trans->transid, level - 1); |
31840ae1 ZY |
929 | BUG_ON(ret); |
930 | ||
0b86a832 | 931 | add_root_to_dirty_list(root); |
925baedd | 932 | btrfs_tree_unlock(child); |
b4ce94de | 933 | |
925baedd | 934 | path->locks[level] = 0; |
bb803951 | 935 | path->nodes[level] = NULL; |
5f39d397 | 936 | clean_tree_block(trans, root, mid); |
925baedd | 937 | btrfs_tree_unlock(mid); |
bb803951 | 938 | /* once for the path */ |
5f39d397 | 939 | free_extent_buffer(mid); |
7bb86316 | 940 | ret = btrfs_free_extent(trans, root, mid->start, mid->len, |
31840ae1 | 941 | mid->start, root->root_key.objectid, |
3bb1a1bc YZ |
942 | btrfs_header_generation(mid), |
943 | level, 1); | |
bb803951 | 944 | /* once for the root ptr */ |
5f39d397 | 945 | free_extent_buffer(mid); |
db94535d | 946 | return ret; |
bb803951 | 947 | } |
5f39d397 | 948 | if (btrfs_header_nritems(mid) > |
123abc88 | 949 | BTRFS_NODEPTRS_PER_BLOCK(root) / 4) |
bb803951 CM |
950 | return 0; |
951 | ||
5f39d397 | 952 | if (btrfs_header_nritems(mid) < 2) |
54aa1f4d CM |
953 | err_on_enospc = 1; |
954 | ||
5f39d397 CM |
955 | left = read_node_slot(root, parent, pslot - 1); |
956 | if (left) { | |
925baedd | 957 | btrfs_tree_lock(left); |
b4ce94de | 958 | btrfs_set_lock_blocking(left); |
5f39d397 | 959 | wret = btrfs_cow_block(trans, root, left, |
9fa8cfe7 | 960 | parent, pslot - 1, &left); |
54aa1f4d CM |
961 | if (wret) { |
962 | ret = wret; | |
963 | goto enospc; | |
964 | } | |
2cc58cf2 | 965 | } |
5f39d397 CM |
966 | right = read_node_slot(root, parent, pslot + 1); |
967 | if (right) { | |
925baedd | 968 | btrfs_tree_lock(right); |
b4ce94de | 969 | btrfs_set_lock_blocking(right); |
5f39d397 | 970 | wret = btrfs_cow_block(trans, root, right, |
9fa8cfe7 | 971 | parent, pslot + 1, &right); |
2cc58cf2 CM |
972 | if (wret) { |
973 | ret = wret; | |
974 | goto enospc; | |
975 | } | |
976 | } | |
977 | ||
978 | /* first, try to make some room in the middle buffer */ | |
5f39d397 CM |
979 | if (left) { |
980 | orig_slot += btrfs_header_nritems(left); | |
bce4eae9 | 981 | wret = push_node_left(trans, root, left, mid, 1); |
79f95c82 CM |
982 | if (wret < 0) |
983 | ret = wret; | |
5f39d397 | 984 | if (btrfs_header_nritems(mid) < 2) |
54aa1f4d | 985 | err_on_enospc = 1; |
bb803951 | 986 | } |
79f95c82 CM |
987 | |
988 | /* | |
989 | * then try to empty the right most buffer into the middle | |
990 | */ | |
5f39d397 | 991 | if (right) { |
971a1f66 | 992 | wret = push_node_left(trans, root, mid, right, 1); |
54aa1f4d | 993 | if (wret < 0 && wret != -ENOSPC) |
79f95c82 | 994 | ret = wret; |
5f39d397 | 995 | if (btrfs_header_nritems(right) == 0) { |
db94535d | 996 | u64 bytenr = right->start; |
7bb86316 | 997 | u64 generation = btrfs_header_generation(parent); |
db94535d CM |
998 | u32 blocksize = right->len; |
999 | ||
5f39d397 | 1000 | clean_tree_block(trans, root, right); |
925baedd | 1001 | btrfs_tree_unlock(right); |
5f39d397 | 1002 | free_extent_buffer(right); |
bb803951 | 1003 | right = NULL; |
e089f05c CM |
1004 | wret = del_ptr(trans, root, path, level + 1, pslot + |
1005 | 1); | |
bb803951 CM |
1006 | if (wret) |
1007 | ret = wret; | |
db94535d | 1008 | wret = btrfs_free_extent(trans, root, bytenr, |
31840ae1 | 1009 | blocksize, parent->start, |
7bb86316 | 1010 | btrfs_header_owner(parent), |
3bb1a1bc | 1011 | generation, level, 1); |
bb803951 CM |
1012 | if (wret) |
1013 | ret = wret; | |
1014 | } else { | |
5f39d397 CM |
1015 | struct btrfs_disk_key right_key; |
1016 | btrfs_node_key(right, &right_key, 0); | |
1017 | btrfs_set_node_key(parent, &right_key, pslot + 1); | |
1018 | btrfs_mark_buffer_dirty(parent); | |
bb803951 CM |
1019 | } |
1020 | } | |
5f39d397 | 1021 | if (btrfs_header_nritems(mid) == 1) { |
79f95c82 CM |
1022 | /* |
1023 | * we're not allowed to leave a node with one item in the | |
1024 | * tree during a delete. A deletion from lower in the tree | |
1025 | * could try to delete the only pointer in this node. | |
1026 | * So, pull some keys from the left. | |
1027 | * There has to be a left pointer at this point because | |
1028 | * otherwise we would have pulled some pointers from the | |
1029 | * right | |
1030 | */ | |
5f39d397 CM |
1031 | BUG_ON(!left); |
1032 | wret = balance_node_right(trans, root, mid, left); | |
54aa1f4d | 1033 | if (wret < 0) { |
79f95c82 | 1034 | ret = wret; |
54aa1f4d CM |
1035 | goto enospc; |
1036 | } | |
bce4eae9 CM |
1037 | if (wret == 1) { |
1038 | wret = push_node_left(trans, root, left, mid, 1); | |
1039 | if (wret < 0) | |
1040 | ret = wret; | |
1041 | } | |
79f95c82 CM |
1042 | BUG_ON(wret == 1); |
1043 | } | |
5f39d397 | 1044 | if (btrfs_header_nritems(mid) == 0) { |
79f95c82 | 1045 | /* we've managed to empty the middle node, drop it */ |
7bb86316 | 1046 | u64 root_gen = btrfs_header_generation(parent); |
db94535d CM |
1047 | u64 bytenr = mid->start; |
1048 | u32 blocksize = mid->len; | |
925baedd | 1049 | |
5f39d397 | 1050 | clean_tree_block(trans, root, mid); |
925baedd | 1051 | btrfs_tree_unlock(mid); |
5f39d397 | 1052 | free_extent_buffer(mid); |
bb803951 | 1053 | mid = NULL; |
e089f05c | 1054 | wret = del_ptr(trans, root, path, level + 1, pslot); |
bb803951 CM |
1055 | if (wret) |
1056 | ret = wret; | |
7bb86316 | 1057 | wret = btrfs_free_extent(trans, root, bytenr, blocksize, |
31840ae1 | 1058 | parent->start, |
7bb86316 | 1059 | btrfs_header_owner(parent), |
3bb1a1bc | 1060 | root_gen, level, 1); |
bb803951 CM |
1061 | if (wret) |
1062 | ret = wret; | |
79f95c82 CM |
1063 | } else { |
1064 | /* update the parent key to reflect our changes */ | |
5f39d397 CM |
1065 | struct btrfs_disk_key mid_key; |
1066 | btrfs_node_key(mid, &mid_key, 0); | |
1067 | btrfs_set_node_key(parent, &mid_key, pslot); | |
1068 | btrfs_mark_buffer_dirty(parent); | |
79f95c82 | 1069 | } |
bb803951 | 1070 | |
79f95c82 | 1071 | /* update the path */ |
5f39d397 CM |
1072 | if (left) { |
1073 | if (btrfs_header_nritems(left) > orig_slot) { | |
1074 | extent_buffer_get(left); | |
925baedd | 1075 | /* left was locked after cow */ |
5f39d397 | 1076 | path->nodes[level] = left; |
bb803951 CM |
1077 | path->slots[level + 1] -= 1; |
1078 | path->slots[level] = orig_slot; | |
925baedd CM |
1079 | if (mid) { |
1080 | btrfs_tree_unlock(mid); | |
5f39d397 | 1081 | free_extent_buffer(mid); |
925baedd | 1082 | } |
bb803951 | 1083 | } else { |
5f39d397 | 1084 | orig_slot -= btrfs_header_nritems(left); |
bb803951 CM |
1085 | path->slots[level] = orig_slot; |
1086 | } | |
1087 | } | |
79f95c82 | 1088 | /* double check we haven't messed things up */ |
123abc88 | 1089 | check_block(root, path, level); |
e20d96d6 | 1090 | if (orig_ptr != |
5f39d397 | 1091 | btrfs_node_blockptr(path->nodes[level], path->slots[level])) |
79f95c82 | 1092 | BUG(); |
54aa1f4d | 1093 | enospc: |
925baedd CM |
1094 | if (right) { |
1095 | btrfs_tree_unlock(right); | |
5f39d397 | 1096 | free_extent_buffer(right); |
925baedd CM |
1097 | } |
1098 | if (left) { | |
1099 | if (path->nodes[level] != left) | |
1100 | btrfs_tree_unlock(left); | |
5f39d397 | 1101 | free_extent_buffer(left); |
925baedd | 1102 | } |
bb803951 CM |
1103 | return ret; |
1104 | } | |
1105 | ||
d352ac68 CM |
1106 | /* Node balancing for insertion. Here we only split or push nodes around |
1107 | * when they are completely full. This is also done top down, so we | |
1108 | * have to be pessimistic. | |
1109 | */ | |
d397712b | 1110 | static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans, |
98ed5174 CM |
1111 | struct btrfs_root *root, |
1112 | struct btrfs_path *path, int level) | |
e66f709b | 1113 | { |
5f39d397 CM |
1114 | struct extent_buffer *right = NULL; |
1115 | struct extent_buffer *mid; | |
1116 | struct extent_buffer *left = NULL; | |
1117 | struct extent_buffer *parent = NULL; | |
e66f709b CM |
1118 | int ret = 0; |
1119 | int wret; | |
1120 | int pslot; | |
1121 | int orig_slot = path->slots[level]; | |
1122 | u64 orig_ptr; | |
1123 | ||
1124 | if (level == 0) | |
1125 | return 1; | |
1126 | ||
5f39d397 | 1127 | mid = path->nodes[level]; |
7bb86316 | 1128 | WARN_ON(btrfs_header_generation(mid) != trans->transid); |
e66f709b CM |
1129 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
1130 | ||
1131 | if (level < BTRFS_MAX_LEVEL - 1) | |
5f39d397 | 1132 | parent = path->nodes[level + 1]; |
e66f709b CM |
1133 | pslot = path->slots[level + 1]; |
1134 | ||
5f39d397 | 1135 | if (!parent) |
e66f709b | 1136 | return 1; |
e66f709b | 1137 | |
5f39d397 | 1138 | left = read_node_slot(root, parent, pslot - 1); |
e66f709b CM |
1139 | |
1140 | /* first, try to make some room in the middle buffer */ | |
5f39d397 | 1141 | if (left) { |
e66f709b | 1142 | u32 left_nr; |
925baedd CM |
1143 | |
1144 | btrfs_tree_lock(left); | |
b4ce94de CM |
1145 | btrfs_set_lock_blocking(left); |
1146 | ||
5f39d397 | 1147 | left_nr = btrfs_header_nritems(left); |
33ade1f8 CM |
1148 | if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
1149 | wret = 1; | |
1150 | } else { | |
5f39d397 | 1151 | ret = btrfs_cow_block(trans, root, left, parent, |
9fa8cfe7 | 1152 | pslot - 1, &left); |
54aa1f4d CM |
1153 | if (ret) |
1154 | wret = 1; | |
1155 | else { | |
54aa1f4d | 1156 | wret = push_node_left(trans, root, |
971a1f66 | 1157 | left, mid, 0); |
54aa1f4d | 1158 | } |
33ade1f8 | 1159 | } |
e66f709b CM |
1160 | if (wret < 0) |
1161 | ret = wret; | |
1162 | if (wret == 0) { | |
5f39d397 | 1163 | struct btrfs_disk_key disk_key; |
e66f709b | 1164 | orig_slot += left_nr; |
5f39d397 CM |
1165 | btrfs_node_key(mid, &disk_key, 0); |
1166 | btrfs_set_node_key(parent, &disk_key, pslot); | |
1167 | btrfs_mark_buffer_dirty(parent); | |
1168 | if (btrfs_header_nritems(left) > orig_slot) { | |
1169 | path->nodes[level] = left; | |
e66f709b CM |
1170 | path->slots[level + 1] -= 1; |
1171 | path->slots[level] = orig_slot; | |
925baedd | 1172 | btrfs_tree_unlock(mid); |
5f39d397 | 1173 | free_extent_buffer(mid); |
e66f709b CM |
1174 | } else { |
1175 | orig_slot -= | |
5f39d397 | 1176 | btrfs_header_nritems(left); |
e66f709b | 1177 | path->slots[level] = orig_slot; |
925baedd | 1178 | btrfs_tree_unlock(left); |
5f39d397 | 1179 | free_extent_buffer(left); |
e66f709b | 1180 | } |
e66f709b CM |
1181 | return 0; |
1182 | } | |
925baedd | 1183 | btrfs_tree_unlock(left); |
5f39d397 | 1184 | free_extent_buffer(left); |
e66f709b | 1185 | } |
925baedd | 1186 | right = read_node_slot(root, parent, pslot + 1); |
e66f709b CM |
1187 | |
1188 | /* | |
1189 | * then try to empty the right most buffer into the middle | |
1190 | */ | |
5f39d397 | 1191 | if (right) { |
33ade1f8 | 1192 | u32 right_nr; |
b4ce94de | 1193 | |
925baedd | 1194 | btrfs_tree_lock(right); |
b4ce94de CM |
1195 | btrfs_set_lock_blocking(right); |
1196 | ||
5f39d397 | 1197 | right_nr = btrfs_header_nritems(right); |
33ade1f8 CM |
1198 | if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
1199 | wret = 1; | |
1200 | } else { | |
5f39d397 CM |
1201 | ret = btrfs_cow_block(trans, root, right, |
1202 | parent, pslot + 1, | |
9fa8cfe7 | 1203 | &right); |
54aa1f4d CM |
1204 | if (ret) |
1205 | wret = 1; | |
1206 | else { | |
54aa1f4d | 1207 | wret = balance_node_right(trans, root, |
5f39d397 | 1208 | right, mid); |
54aa1f4d | 1209 | } |
33ade1f8 | 1210 | } |
e66f709b CM |
1211 | if (wret < 0) |
1212 | ret = wret; | |
1213 | if (wret == 0) { | |
5f39d397 CM |
1214 | struct btrfs_disk_key disk_key; |
1215 | ||
1216 | btrfs_node_key(right, &disk_key, 0); | |
1217 | btrfs_set_node_key(parent, &disk_key, pslot + 1); | |
1218 | btrfs_mark_buffer_dirty(parent); | |
1219 | ||
1220 | if (btrfs_header_nritems(mid) <= orig_slot) { | |
1221 | path->nodes[level] = right; | |
e66f709b CM |
1222 | path->slots[level + 1] += 1; |
1223 | path->slots[level] = orig_slot - | |
5f39d397 | 1224 | btrfs_header_nritems(mid); |
925baedd | 1225 | btrfs_tree_unlock(mid); |
5f39d397 | 1226 | free_extent_buffer(mid); |
e66f709b | 1227 | } else { |
925baedd | 1228 | btrfs_tree_unlock(right); |
5f39d397 | 1229 | free_extent_buffer(right); |
e66f709b | 1230 | } |
e66f709b CM |
1231 | return 0; |
1232 | } | |
925baedd | 1233 | btrfs_tree_unlock(right); |
5f39d397 | 1234 | free_extent_buffer(right); |
e66f709b | 1235 | } |
e66f709b CM |
1236 | return 1; |
1237 | } | |
1238 | ||
3c69faec | 1239 | /* |
d352ac68 CM |
1240 | * readahead one full node of leaves, finding things that are close |
1241 | * to the block in 'slot', and triggering ra on them. | |
3c69faec | 1242 | */ |
e02119d5 CM |
1243 | static noinline void reada_for_search(struct btrfs_root *root, |
1244 | struct btrfs_path *path, | |
1245 | int level, int slot, u64 objectid) | |
3c69faec | 1246 | { |
5f39d397 | 1247 | struct extent_buffer *node; |
01f46658 | 1248 | struct btrfs_disk_key disk_key; |
3c69faec | 1249 | u32 nritems; |
3c69faec | 1250 | u64 search; |
a7175319 | 1251 | u64 target; |
6b80053d | 1252 | u64 nread = 0; |
3c69faec | 1253 | int direction = path->reada; |
5f39d397 | 1254 | struct extent_buffer *eb; |
6b80053d CM |
1255 | u32 nr; |
1256 | u32 blocksize; | |
1257 | u32 nscan = 0; | |
db94535d | 1258 | |
a6b6e75e | 1259 | if (level != 1) |
6702ed49 CM |
1260 | return; |
1261 | ||
1262 | if (!path->nodes[level]) | |
3c69faec CM |
1263 | return; |
1264 | ||
5f39d397 | 1265 | node = path->nodes[level]; |
925baedd | 1266 | |
3c69faec | 1267 | search = btrfs_node_blockptr(node, slot); |
6b80053d CM |
1268 | blocksize = btrfs_level_size(root, level - 1); |
1269 | eb = btrfs_find_tree_block(root, search, blocksize); | |
5f39d397 CM |
1270 | if (eb) { |
1271 | free_extent_buffer(eb); | |
3c69faec CM |
1272 | return; |
1273 | } | |
1274 | ||
a7175319 | 1275 | target = search; |
6b80053d | 1276 | |
5f39d397 | 1277 | nritems = btrfs_header_nritems(node); |
6b80053d | 1278 | nr = slot; |
d397712b | 1279 | while (1) { |
6b80053d CM |
1280 | if (direction < 0) { |
1281 | if (nr == 0) | |
1282 | break; | |
1283 | nr--; | |
1284 | } else if (direction > 0) { | |
1285 | nr++; | |
1286 | if (nr >= nritems) | |
1287 | break; | |
3c69faec | 1288 | } |
01f46658 CM |
1289 | if (path->reada < 0 && objectid) { |
1290 | btrfs_node_key(node, &disk_key, nr); | |
1291 | if (btrfs_disk_key_objectid(&disk_key) != objectid) | |
1292 | break; | |
1293 | } | |
6b80053d | 1294 | search = btrfs_node_blockptr(node, nr); |
a7175319 CM |
1295 | if ((search <= target && target - search <= 65536) || |
1296 | (search > target && search - target <= 65536)) { | |
ca7a79ad CM |
1297 | readahead_tree_block(root, search, blocksize, |
1298 | btrfs_node_ptr_generation(node, nr)); | |
6b80053d CM |
1299 | nread += blocksize; |
1300 | } | |
1301 | nscan++; | |
a7175319 | 1302 | if ((nread > 65536 || nscan > 32)) |
6b80053d | 1303 | break; |
3c69faec CM |
1304 | } |
1305 | } | |
925baedd | 1306 | |
b4ce94de CM |
1307 | /* |
1308 | * returns -EAGAIN if it had to drop the path, or zero if everything was in | |
1309 | * cache | |
1310 | */ | |
1311 | static noinline int reada_for_balance(struct btrfs_root *root, | |
1312 | struct btrfs_path *path, int level) | |
1313 | { | |
1314 | int slot; | |
1315 | int nritems; | |
1316 | struct extent_buffer *parent; | |
1317 | struct extent_buffer *eb; | |
1318 | u64 gen; | |
1319 | u64 block1 = 0; | |
1320 | u64 block2 = 0; | |
1321 | int ret = 0; | |
1322 | int blocksize; | |
1323 | ||
1324 | parent = path->nodes[level - 1]; | |
1325 | if (!parent) | |
1326 | return 0; | |
1327 | ||
1328 | nritems = btrfs_header_nritems(parent); | |
1329 | slot = path->slots[level]; | |
1330 | blocksize = btrfs_level_size(root, level); | |
1331 | ||
1332 | if (slot > 0) { | |
1333 | block1 = btrfs_node_blockptr(parent, slot - 1); | |
1334 | gen = btrfs_node_ptr_generation(parent, slot - 1); | |
1335 | eb = btrfs_find_tree_block(root, block1, blocksize); | |
1336 | if (eb && btrfs_buffer_uptodate(eb, gen)) | |
1337 | block1 = 0; | |
1338 | free_extent_buffer(eb); | |
1339 | } | |
1340 | if (slot < nritems) { | |
1341 | block2 = btrfs_node_blockptr(parent, slot + 1); | |
1342 | gen = btrfs_node_ptr_generation(parent, slot + 1); | |
1343 | eb = btrfs_find_tree_block(root, block2, blocksize); | |
1344 | if (eb && btrfs_buffer_uptodate(eb, gen)) | |
1345 | block2 = 0; | |
1346 | free_extent_buffer(eb); | |
1347 | } | |
1348 | if (block1 || block2) { | |
1349 | ret = -EAGAIN; | |
1350 | btrfs_release_path(root, path); | |
1351 | if (block1) | |
1352 | readahead_tree_block(root, block1, blocksize, 0); | |
1353 | if (block2) | |
1354 | readahead_tree_block(root, block2, blocksize, 0); | |
1355 | ||
1356 | if (block1) { | |
1357 | eb = read_tree_block(root, block1, blocksize, 0); | |
1358 | free_extent_buffer(eb); | |
1359 | } | |
1360 | if (block1) { | |
1361 | eb = read_tree_block(root, block2, blocksize, 0); | |
1362 | free_extent_buffer(eb); | |
1363 | } | |
1364 | } | |
1365 | return ret; | |
1366 | } | |
1367 | ||
1368 | ||
d352ac68 | 1369 | /* |
d397712b CM |
1370 | * when we walk down the tree, it is usually safe to unlock the higher layers |
1371 | * in the tree. The exceptions are when our path goes through slot 0, because | |
1372 | * operations on the tree might require changing key pointers higher up in the | |
1373 | * tree. | |
d352ac68 | 1374 | * |
d397712b CM |
1375 | * callers might also have set path->keep_locks, which tells this code to keep |
1376 | * the lock if the path points to the last slot in the block. This is part of | |
1377 | * walking through the tree, and selecting the next slot in the higher block. | |
d352ac68 | 1378 | * |
d397712b CM |
1379 | * lowest_unlock sets the lowest level in the tree we're allowed to unlock. so |
1380 | * if lowest_unlock is 1, level 0 won't be unlocked | |
d352ac68 | 1381 | */ |
e02119d5 CM |
1382 | static noinline void unlock_up(struct btrfs_path *path, int level, |
1383 | int lowest_unlock) | |
925baedd CM |
1384 | { |
1385 | int i; | |
1386 | int skip_level = level; | |
051e1b9f | 1387 | int no_skips = 0; |
925baedd CM |
1388 | struct extent_buffer *t; |
1389 | ||
1390 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { | |
1391 | if (!path->nodes[i]) | |
1392 | break; | |
1393 | if (!path->locks[i]) | |
1394 | break; | |
051e1b9f | 1395 | if (!no_skips && path->slots[i] == 0) { |
925baedd CM |
1396 | skip_level = i + 1; |
1397 | continue; | |
1398 | } | |
051e1b9f | 1399 | if (!no_skips && path->keep_locks) { |
925baedd CM |
1400 | u32 nritems; |
1401 | t = path->nodes[i]; | |
1402 | nritems = btrfs_header_nritems(t); | |
051e1b9f | 1403 | if (nritems < 1 || path->slots[i] >= nritems - 1) { |
925baedd CM |
1404 | skip_level = i + 1; |
1405 | continue; | |
1406 | } | |
1407 | } | |
051e1b9f CM |
1408 | if (skip_level < i && i >= lowest_unlock) |
1409 | no_skips = 1; | |
1410 | ||
925baedd CM |
1411 | t = path->nodes[i]; |
1412 | if (i >= lowest_unlock && i > skip_level && path->locks[i]) { | |
1413 | btrfs_tree_unlock(t); | |
1414 | path->locks[i] = 0; | |
1415 | } | |
1416 | } | |
1417 | } | |
1418 | ||
b4ce94de CM |
1419 | /* |
1420 | * This releases any locks held in the path starting at level and | |
1421 | * going all the way up to the root. | |
1422 | * | |
1423 | * btrfs_search_slot will keep the lock held on higher nodes in a few | |
1424 | * corner cases, such as COW of the block at slot zero in the node. This | |
1425 | * ignores those rules, and it should only be called when there are no | |
1426 | * more updates to be done higher up in the tree. | |
1427 | */ | |
1428 | noinline void btrfs_unlock_up_safe(struct btrfs_path *path, int level) | |
1429 | { | |
1430 | int i; | |
1431 | ||
1432 | if (path->keep_locks || path->lowest_level) | |
1433 | return; | |
1434 | ||
1435 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { | |
1436 | if (!path->nodes[i]) | |
12f4dacc | 1437 | continue; |
b4ce94de | 1438 | if (!path->locks[i]) |
12f4dacc | 1439 | continue; |
b4ce94de CM |
1440 | btrfs_tree_unlock(path->nodes[i]); |
1441 | path->locks[i] = 0; | |
1442 | } | |
1443 | } | |
1444 | ||
74123bd7 CM |
1445 | /* |
1446 | * look for key in the tree. path is filled in with nodes along the way | |
1447 | * if key is found, we return zero and you can find the item in the leaf | |
1448 | * level of the path (level 0) | |
1449 | * | |
1450 | * If the key isn't found, the path points to the slot where it should | |
aa5d6bed CM |
1451 | * be inserted, and 1 is returned. If there are other errors during the |
1452 | * search a negative error number is returned. | |
97571fd0 CM |
1453 | * |
1454 | * if ins_len > 0, nodes and leaves will be split as we walk down the | |
1455 | * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if | |
1456 | * possible) | |
74123bd7 | 1457 | */ |
e089f05c CM |
1458 | int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root |
1459 | *root, struct btrfs_key *key, struct btrfs_path *p, int | |
1460 | ins_len, int cow) | |
be0e5c09 | 1461 | { |
5f39d397 | 1462 | struct extent_buffer *b; |
051e1b9f | 1463 | struct extent_buffer *tmp; |
be0e5c09 CM |
1464 | int slot; |
1465 | int ret; | |
1466 | int level; | |
3c69faec | 1467 | int should_reada = p->reada; |
925baedd | 1468 | int lowest_unlock = 1; |
594a24eb | 1469 | int blocksize; |
9f3a7427 | 1470 | u8 lowest_level = 0; |
594a24eb CM |
1471 | u64 blocknr; |
1472 | u64 gen; | |
9f3a7427 | 1473 | |
6702ed49 | 1474 | lowest_level = p->lowest_level; |
323ac95b | 1475 | WARN_ON(lowest_level && ins_len > 0); |
22b0ebda | 1476 | WARN_ON(p->nodes[0] != NULL); |
25179201 | 1477 | |
925baedd CM |
1478 | if (ins_len < 0) |
1479 | lowest_unlock = 2; | |
65b51a00 | 1480 | |
bb803951 | 1481 | again: |
5cd57b2c CM |
1482 | if (p->skip_locking) |
1483 | b = btrfs_root_node(root); | |
1484 | else | |
1485 | b = btrfs_lock_root_node(root); | |
925baedd | 1486 | |
eb60ceac | 1487 | while (b) { |
5f39d397 | 1488 | level = btrfs_header_level(b); |
65b51a00 CM |
1489 | |
1490 | /* | |
1491 | * setup the path here so we can release it under lock | |
1492 | * contention with the cow code | |
1493 | */ | |
1494 | p->nodes[level] = b; | |
1495 | if (!p->skip_locking) | |
1496 | p->locks[level] = 1; | |
1497 | ||
02217ed2 CM |
1498 | if (cow) { |
1499 | int wret; | |
65b51a00 CM |
1500 | |
1501 | /* is a cow on this block not required */ | |
65b51a00 | 1502 | if (btrfs_header_generation(b) == trans->transid && |
5b21f2ed | 1503 | btrfs_header_owner(b) == root->root_key.objectid && |
65b51a00 | 1504 | !btrfs_header_flag(b, BTRFS_HEADER_FLAG_WRITTEN)) { |
65b51a00 CM |
1505 | goto cow_done; |
1506 | } | |
b4ce94de CM |
1507 | btrfs_set_path_blocking(p); |
1508 | ||
e20d96d6 CM |
1509 | wret = btrfs_cow_block(trans, root, b, |
1510 | p->nodes[level + 1], | |
9fa8cfe7 | 1511 | p->slots[level + 1], &b); |
54aa1f4d | 1512 | if (wret) { |
5f39d397 | 1513 | free_extent_buffer(b); |
65b51a00 CM |
1514 | ret = wret; |
1515 | goto done; | |
54aa1f4d | 1516 | } |
02217ed2 | 1517 | } |
65b51a00 | 1518 | cow_done: |
02217ed2 | 1519 | BUG_ON(!cow && ins_len); |
5f39d397 | 1520 | if (level != btrfs_header_level(b)) |
2c90e5d6 | 1521 | WARN_ON(1); |
5f39d397 | 1522 | level = btrfs_header_level(b); |
65b51a00 | 1523 | |
eb60ceac | 1524 | p->nodes[level] = b; |
5cd57b2c CM |
1525 | if (!p->skip_locking) |
1526 | p->locks[level] = 1; | |
65b51a00 | 1527 | |
4008c04a | 1528 | btrfs_clear_path_blocking(p, NULL); |
b4ce94de CM |
1529 | |
1530 | /* | |
1531 | * we have a lock on b and as long as we aren't changing | |
1532 | * the tree, there is no way to for the items in b to change. | |
1533 | * It is safe to drop the lock on our parent before we | |
1534 | * go through the expensive btree search on b. | |
1535 | * | |
1536 | * If cow is true, then we might be changing slot zero, | |
1537 | * which may require changing the parent. So, we can't | |
1538 | * drop the lock until after we know which slot we're | |
1539 | * operating on. | |
1540 | */ | |
1541 | if (!cow) | |
1542 | btrfs_unlock_up_safe(p, level + 1); | |
1543 | ||
123abc88 | 1544 | ret = check_block(root, p, level); |
65b51a00 CM |
1545 | if (ret) { |
1546 | ret = -1; | |
1547 | goto done; | |
1548 | } | |
925baedd | 1549 | |
5f39d397 | 1550 | ret = bin_search(b, key, level, &slot); |
b4ce94de | 1551 | |
5f39d397 | 1552 | if (level != 0) { |
be0e5c09 CM |
1553 | if (ret && slot > 0) |
1554 | slot -= 1; | |
1555 | p->slots[level] = slot; | |
459931ec CM |
1556 | if ((p->search_for_split || ins_len > 0) && |
1557 | btrfs_header_nritems(b) >= | |
1514794e | 1558 | BTRFS_NODEPTRS_PER_BLOCK(root) - 3) { |
b4ce94de CM |
1559 | int sret; |
1560 | ||
1561 | sret = reada_for_balance(root, p, level); | |
1562 | if (sret) | |
1563 | goto again; | |
1564 | ||
1565 | btrfs_set_path_blocking(p); | |
1566 | sret = split_node(trans, root, p, level); | |
4008c04a | 1567 | btrfs_clear_path_blocking(p, NULL); |
b4ce94de | 1568 | |
5c680ed6 | 1569 | BUG_ON(sret > 0); |
65b51a00 CM |
1570 | if (sret) { |
1571 | ret = sret; | |
1572 | goto done; | |
1573 | } | |
5c680ed6 | 1574 | b = p->nodes[level]; |
5c680ed6 | 1575 | slot = p->slots[level]; |
7b78c170 CM |
1576 | } else if (ins_len < 0 && |
1577 | btrfs_header_nritems(b) < | |
1578 | BTRFS_NODEPTRS_PER_BLOCK(root) / 4) { | |
b4ce94de CM |
1579 | int sret; |
1580 | ||
1581 | sret = reada_for_balance(root, p, level); | |
1582 | if (sret) | |
1583 | goto again; | |
1584 | ||
1585 | btrfs_set_path_blocking(p); | |
1586 | sret = balance_level(trans, root, p, level); | |
4008c04a | 1587 | btrfs_clear_path_blocking(p, NULL); |
b4ce94de | 1588 | |
65b51a00 CM |
1589 | if (sret) { |
1590 | ret = sret; | |
1591 | goto done; | |
1592 | } | |
bb803951 | 1593 | b = p->nodes[level]; |
f510cfec CM |
1594 | if (!b) { |
1595 | btrfs_release_path(NULL, p); | |
bb803951 | 1596 | goto again; |
f510cfec | 1597 | } |
bb803951 | 1598 | slot = p->slots[level]; |
5f39d397 | 1599 | BUG_ON(btrfs_header_nritems(b) == 1); |
5c680ed6 | 1600 | } |
f9efa9c7 CM |
1601 | unlock_up(p, level, lowest_unlock); |
1602 | ||
9f3a7427 | 1603 | /* this is only true while dropping a snapshot */ |
925baedd | 1604 | if (level == lowest_level) { |
5b21f2ed ZY |
1605 | ret = 0; |
1606 | goto done; | |
925baedd | 1607 | } |
ca7a79ad | 1608 | |
594a24eb CM |
1609 | blocknr = btrfs_node_blockptr(b, slot); |
1610 | gen = btrfs_node_ptr_generation(b, slot); | |
1611 | blocksize = btrfs_level_size(root, level - 1); | |
1612 | ||
1613 | tmp = btrfs_find_tree_block(root, blocknr, blocksize); | |
1614 | if (tmp && btrfs_buffer_uptodate(tmp, gen)) { | |
051e1b9f CM |
1615 | b = tmp; |
1616 | } else { | |
1617 | /* | |
1618 | * reduce lock contention at high levels | |
1619 | * of the btree by dropping locks before | |
1620 | * we read. | |
1621 | */ | |
b4ce94de | 1622 | if (level > 0) { |
051e1b9f | 1623 | btrfs_release_path(NULL, p); |
594a24eb CM |
1624 | if (tmp) |
1625 | free_extent_buffer(tmp); | |
f9efa9c7 CM |
1626 | if (should_reada) |
1627 | reada_for_search(root, p, | |
1628 | level, slot, | |
1629 | key->objectid); | |
1630 | ||
594a24eb CM |
1631 | tmp = read_tree_block(root, blocknr, |
1632 | blocksize, gen); | |
051e1b9f CM |
1633 | if (tmp) |
1634 | free_extent_buffer(tmp); | |
1635 | goto again; | |
1636 | } else { | |
b4ce94de | 1637 | btrfs_set_path_blocking(p); |
a74a4b97 CM |
1638 | if (tmp) |
1639 | free_extent_buffer(tmp); | |
f9efa9c7 CM |
1640 | if (should_reada) |
1641 | reada_for_search(root, p, | |
1642 | level, slot, | |
1643 | key->objectid); | |
051e1b9f CM |
1644 | b = read_node_slot(root, b, slot); |
1645 | } | |
1646 | } | |
b4ce94de CM |
1647 | if (!p->skip_locking) { |
1648 | int lret; | |
1649 | ||
4008c04a | 1650 | btrfs_clear_path_blocking(p, NULL); |
b4ce94de CM |
1651 | lret = btrfs_try_spin_lock(b); |
1652 | ||
1653 | if (!lret) { | |
1654 | btrfs_set_path_blocking(p); | |
1655 | btrfs_tree_lock(b); | |
4008c04a | 1656 | btrfs_clear_path_blocking(p, b); |
b4ce94de CM |
1657 | } |
1658 | } | |
be0e5c09 CM |
1659 | } else { |
1660 | p->slots[level] = slot; | |
87b29b20 YZ |
1661 | if (ins_len > 0 && |
1662 | btrfs_leaf_free_space(root, b) < ins_len) { | |
b4ce94de CM |
1663 | int sret; |
1664 | ||
1665 | btrfs_set_path_blocking(p); | |
1666 | sret = split_leaf(trans, root, key, | |
cc0c5538 | 1667 | p, ins_len, ret == 0); |
4008c04a | 1668 | btrfs_clear_path_blocking(p, NULL); |
b4ce94de | 1669 | |
5c680ed6 | 1670 | BUG_ON(sret > 0); |
65b51a00 CM |
1671 | if (sret) { |
1672 | ret = sret; | |
1673 | goto done; | |
1674 | } | |
5c680ed6 | 1675 | } |
459931ec CM |
1676 | if (!p->search_for_split) |
1677 | unlock_up(p, level, lowest_unlock); | |
65b51a00 | 1678 | goto done; |
be0e5c09 CM |
1679 | } |
1680 | } | |
65b51a00 CM |
1681 | ret = 1; |
1682 | done: | |
b4ce94de CM |
1683 | /* |
1684 | * we don't really know what they plan on doing with the path | |
1685 | * from here on, so for now just mark it as blocking | |
1686 | */ | |
1687 | btrfs_set_path_blocking(p); | |
65b51a00 | 1688 | return ret; |
be0e5c09 CM |
1689 | } |
1690 | ||
1a40e23b ZY |
1691 | int btrfs_merge_path(struct btrfs_trans_handle *trans, |
1692 | struct btrfs_root *root, | |
1693 | struct btrfs_key *node_keys, | |
1694 | u64 *nodes, int lowest_level) | |
1695 | { | |
1696 | struct extent_buffer *eb; | |
1697 | struct extent_buffer *parent; | |
1698 | struct btrfs_key key; | |
1699 | u64 bytenr; | |
1700 | u64 generation; | |
1701 | u32 blocksize; | |
1702 | int level; | |
1703 | int slot; | |
1704 | int key_match; | |
1705 | int ret; | |
1706 | ||
1707 | eb = btrfs_lock_root_node(root); | |
9fa8cfe7 | 1708 | ret = btrfs_cow_block(trans, root, eb, NULL, 0, &eb); |
1a40e23b ZY |
1709 | BUG_ON(ret); |
1710 | ||
b4ce94de CM |
1711 | btrfs_set_lock_blocking(eb); |
1712 | ||
1a40e23b ZY |
1713 | parent = eb; |
1714 | while (1) { | |
1715 | level = btrfs_header_level(parent); | |
1716 | if (level == 0 || level <= lowest_level) | |
1717 | break; | |
1718 | ||
1719 | ret = bin_search(parent, &node_keys[lowest_level], level, | |
1720 | &slot); | |
1721 | if (ret && slot > 0) | |
1722 | slot--; | |
1723 | ||
1724 | bytenr = btrfs_node_blockptr(parent, slot); | |
1725 | if (nodes[level - 1] == bytenr) | |
1726 | break; | |
1727 | ||
1728 | blocksize = btrfs_level_size(root, level - 1); | |
1729 | generation = btrfs_node_ptr_generation(parent, slot); | |
1730 | btrfs_node_key_to_cpu(eb, &key, slot); | |
1731 | key_match = !memcmp(&key, &node_keys[level - 1], sizeof(key)); | |
1732 | ||
f82d02d9 YZ |
1733 | if (generation == trans->transid) { |
1734 | eb = read_tree_block(root, bytenr, blocksize, | |
1735 | generation); | |
1736 | btrfs_tree_lock(eb); | |
b4ce94de | 1737 | btrfs_set_lock_blocking(eb); |
f82d02d9 YZ |
1738 | } |
1739 | ||
1a40e23b ZY |
1740 | /* |
1741 | * if node keys match and node pointer hasn't been modified | |
1742 | * in the running transaction, we can merge the path. for | |
f82d02d9 YZ |
1743 | * blocks owened by reloc trees, the node pointer check is |
1744 | * skipped, this is because these blocks are fully controlled | |
1745 | * by the space balance code, no one else can modify them. | |
1a40e23b ZY |
1746 | */ |
1747 | if (!nodes[level - 1] || !key_match || | |
1748 | (generation == trans->transid && | |
f82d02d9 YZ |
1749 | btrfs_header_owner(eb) != BTRFS_TREE_RELOC_OBJECTID)) { |
1750 | if (level == 1 || level == lowest_level + 1) { | |
1751 | if (generation == trans->transid) { | |
1752 | btrfs_tree_unlock(eb); | |
1753 | free_extent_buffer(eb); | |
1754 | } | |
1a40e23b | 1755 | break; |
f82d02d9 | 1756 | } |
1a40e23b | 1757 | |
f82d02d9 YZ |
1758 | if (generation != trans->transid) { |
1759 | eb = read_tree_block(root, bytenr, blocksize, | |
1760 | generation); | |
1761 | btrfs_tree_lock(eb); | |
b4ce94de | 1762 | btrfs_set_lock_blocking(eb); |
f82d02d9 | 1763 | } |
1a40e23b ZY |
1764 | |
1765 | ret = btrfs_cow_block(trans, root, eb, parent, slot, | |
9fa8cfe7 | 1766 | &eb); |
1a40e23b ZY |
1767 | BUG_ON(ret); |
1768 | ||
f82d02d9 YZ |
1769 | if (root->root_key.objectid == |
1770 | BTRFS_TREE_RELOC_OBJECTID) { | |
1771 | if (!nodes[level - 1]) { | |
1772 | nodes[level - 1] = eb->start; | |
1773 | memcpy(&node_keys[level - 1], &key, | |
1774 | sizeof(node_keys[0])); | |
1775 | } else { | |
1776 | WARN_ON(1); | |
1777 | } | |
1778 | } | |
1779 | ||
1a40e23b ZY |
1780 | btrfs_tree_unlock(parent); |
1781 | free_extent_buffer(parent); | |
1782 | parent = eb; | |
1783 | continue; | |
1784 | } | |
1785 | ||
1a40e23b ZY |
1786 | btrfs_set_node_blockptr(parent, slot, nodes[level - 1]); |
1787 | btrfs_set_node_ptr_generation(parent, slot, trans->transid); | |
1788 | btrfs_mark_buffer_dirty(parent); | |
1789 | ||
1790 | ret = btrfs_inc_extent_ref(trans, root, | |
1791 | nodes[level - 1], | |
1792 | blocksize, parent->start, | |
1793 | btrfs_header_owner(parent), | |
1794 | btrfs_header_generation(parent), | |
3bb1a1bc | 1795 | level - 1); |
1a40e23b | 1796 | BUG_ON(ret); |
1a40e23b | 1797 | |
f82d02d9 YZ |
1798 | /* |
1799 | * If the block was created in the running transaction, | |
1800 | * it's possible this is the last reference to it, so we | |
1801 | * should drop the subtree. | |
1802 | */ | |
1a40e23b | 1803 | if (generation == trans->transid) { |
f82d02d9 YZ |
1804 | ret = btrfs_drop_subtree(trans, root, eb, parent); |
1805 | BUG_ON(ret); | |
1a40e23b ZY |
1806 | btrfs_tree_unlock(eb); |
1807 | free_extent_buffer(eb); | |
f82d02d9 YZ |
1808 | } else { |
1809 | ret = btrfs_free_extent(trans, root, bytenr, | |
1810 | blocksize, parent->start, | |
1811 | btrfs_header_owner(parent), | |
1812 | btrfs_header_generation(parent), | |
1813 | level - 1, 1); | |
1814 | BUG_ON(ret); | |
1a40e23b ZY |
1815 | } |
1816 | break; | |
1817 | } | |
1818 | btrfs_tree_unlock(parent); | |
1819 | free_extent_buffer(parent); | |
1820 | return 0; | |
1821 | } | |
1822 | ||
74123bd7 CM |
1823 | /* |
1824 | * adjust the pointers going up the tree, starting at level | |
1825 | * making sure the right key of each node is points to 'key'. | |
1826 | * This is used after shifting pointers to the left, so it stops | |
1827 | * fixing up pointers when a given leaf/node is not in slot 0 of the | |
1828 | * higher levels | |
aa5d6bed CM |
1829 | * |
1830 | * If this fails to write a tree block, it returns -1, but continues | |
1831 | * fixing up the blocks in ram so the tree is consistent. | |
74123bd7 | 1832 | */ |
5f39d397 CM |
1833 | static int fixup_low_keys(struct btrfs_trans_handle *trans, |
1834 | struct btrfs_root *root, struct btrfs_path *path, | |
1835 | struct btrfs_disk_key *key, int level) | |
be0e5c09 CM |
1836 | { |
1837 | int i; | |
aa5d6bed | 1838 | int ret = 0; |
5f39d397 CM |
1839 | struct extent_buffer *t; |
1840 | ||
234b63a0 | 1841 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
be0e5c09 | 1842 | int tslot = path->slots[i]; |
eb60ceac | 1843 | if (!path->nodes[i]) |
be0e5c09 | 1844 | break; |
5f39d397 CM |
1845 | t = path->nodes[i]; |
1846 | btrfs_set_node_key(t, key, tslot); | |
d6025579 | 1847 | btrfs_mark_buffer_dirty(path->nodes[i]); |
be0e5c09 CM |
1848 | if (tslot != 0) |
1849 | break; | |
1850 | } | |
aa5d6bed | 1851 | return ret; |
be0e5c09 CM |
1852 | } |
1853 | ||
31840ae1 ZY |
1854 | /* |
1855 | * update item key. | |
1856 | * | |
1857 | * This function isn't completely safe. It's the caller's responsibility | |
1858 | * that the new key won't break the order | |
1859 | */ | |
1860 | int btrfs_set_item_key_safe(struct btrfs_trans_handle *trans, | |
1861 | struct btrfs_root *root, struct btrfs_path *path, | |
1862 | struct btrfs_key *new_key) | |
1863 | { | |
1864 | struct btrfs_disk_key disk_key; | |
1865 | struct extent_buffer *eb; | |
1866 | int slot; | |
1867 | ||
1868 | eb = path->nodes[0]; | |
1869 | slot = path->slots[0]; | |
1870 | if (slot > 0) { | |
1871 | btrfs_item_key(eb, &disk_key, slot - 1); | |
1872 | if (comp_keys(&disk_key, new_key) >= 0) | |
1873 | return -1; | |
1874 | } | |
1875 | if (slot < btrfs_header_nritems(eb) - 1) { | |
1876 | btrfs_item_key(eb, &disk_key, slot + 1); | |
1877 | if (comp_keys(&disk_key, new_key) <= 0) | |
1878 | return -1; | |
1879 | } | |
1880 | ||
1881 | btrfs_cpu_key_to_disk(&disk_key, new_key); | |
1882 | btrfs_set_item_key(eb, &disk_key, slot); | |
1883 | btrfs_mark_buffer_dirty(eb); | |
1884 | if (slot == 0) | |
1885 | fixup_low_keys(trans, root, path, &disk_key, 1); | |
1886 | return 0; | |
1887 | } | |
1888 | ||
74123bd7 CM |
1889 | /* |
1890 | * try to push data from one node into the next node left in the | |
79f95c82 | 1891 | * tree. |
aa5d6bed CM |
1892 | * |
1893 | * returns 0 if some ptrs were pushed left, < 0 if there was some horrible | |
1894 | * error, and > 0 if there was no room in the left hand block. | |
74123bd7 | 1895 | */ |
98ed5174 CM |
1896 | static int push_node_left(struct btrfs_trans_handle *trans, |
1897 | struct btrfs_root *root, struct extent_buffer *dst, | |
971a1f66 | 1898 | struct extent_buffer *src, int empty) |
be0e5c09 | 1899 | { |
be0e5c09 | 1900 | int push_items = 0; |
bb803951 CM |
1901 | int src_nritems; |
1902 | int dst_nritems; | |
aa5d6bed | 1903 | int ret = 0; |
be0e5c09 | 1904 | |
5f39d397 CM |
1905 | src_nritems = btrfs_header_nritems(src); |
1906 | dst_nritems = btrfs_header_nritems(dst); | |
123abc88 | 1907 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
7bb86316 CM |
1908 | WARN_ON(btrfs_header_generation(src) != trans->transid); |
1909 | WARN_ON(btrfs_header_generation(dst) != trans->transid); | |
54aa1f4d | 1910 | |
bce4eae9 | 1911 | if (!empty && src_nritems <= 8) |
971a1f66 CM |
1912 | return 1; |
1913 | ||
d397712b | 1914 | if (push_items <= 0) |
be0e5c09 CM |
1915 | return 1; |
1916 | ||
bce4eae9 | 1917 | if (empty) { |
971a1f66 | 1918 | push_items = min(src_nritems, push_items); |
bce4eae9 CM |
1919 | if (push_items < src_nritems) { |
1920 | /* leave at least 8 pointers in the node if | |
1921 | * we aren't going to empty it | |
1922 | */ | |
1923 | if (src_nritems - push_items < 8) { | |
1924 | if (push_items <= 8) | |
1925 | return 1; | |
1926 | push_items -= 8; | |
1927 | } | |
1928 | } | |
1929 | } else | |
1930 | push_items = min(src_nritems - 8, push_items); | |
79f95c82 | 1931 | |
5f39d397 CM |
1932 | copy_extent_buffer(dst, src, |
1933 | btrfs_node_key_ptr_offset(dst_nritems), | |
1934 | btrfs_node_key_ptr_offset(0), | |
d397712b | 1935 | push_items * sizeof(struct btrfs_key_ptr)); |
5f39d397 | 1936 | |
bb803951 | 1937 | if (push_items < src_nritems) { |
5f39d397 CM |
1938 | memmove_extent_buffer(src, btrfs_node_key_ptr_offset(0), |
1939 | btrfs_node_key_ptr_offset(push_items), | |
1940 | (src_nritems - push_items) * | |
1941 | sizeof(struct btrfs_key_ptr)); | |
1942 | } | |
1943 | btrfs_set_header_nritems(src, src_nritems - push_items); | |
1944 | btrfs_set_header_nritems(dst, dst_nritems + push_items); | |
1945 | btrfs_mark_buffer_dirty(src); | |
1946 | btrfs_mark_buffer_dirty(dst); | |
31840ae1 ZY |
1947 | |
1948 | ret = btrfs_update_ref(trans, root, src, dst, dst_nritems, push_items); | |
1949 | BUG_ON(ret); | |
1950 | ||
79f95c82 CM |
1951 | return ret; |
1952 | } | |
1953 | ||
1954 | /* | |
1955 | * try to push data from one node into the next node right in the | |
1956 | * tree. | |
1957 | * | |
1958 | * returns 0 if some ptrs were pushed, < 0 if there was some horrible | |
1959 | * error, and > 0 if there was no room in the right hand block. | |
1960 | * | |
1961 | * this will only push up to 1/2 the contents of the left node over | |
1962 | */ | |
5f39d397 CM |
1963 | static int balance_node_right(struct btrfs_trans_handle *trans, |
1964 | struct btrfs_root *root, | |
1965 | struct extent_buffer *dst, | |
1966 | struct extent_buffer *src) | |
79f95c82 | 1967 | { |
79f95c82 CM |
1968 | int push_items = 0; |
1969 | int max_push; | |
1970 | int src_nritems; | |
1971 | int dst_nritems; | |
1972 | int ret = 0; | |
79f95c82 | 1973 | |
7bb86316 CM |
1974 | WARN_ON(btrfs_header_generation(src) != trans->transid); |
1975 | WARN_ON(btrfs_header_generation(dst) != trans->transid); | |
1976 | ||
5f39d397 CM |
1977 | src_nritems = btrfs_header_nritems(src); |
1978 | dst_nritems = btrfs_header_nritems(dst); | |
123abc88 | 1979 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
d397712b | 1980 | if (push_items <= 0) |
79f95c82 | 1981 | return 1; |
bce4eae9 | 1982 | |
d397712b | 1983 | if (src_nritems < 4) |
bce4eae9 | 1984 | return 1; |
79f95c82 CM |
1985 | |
1986 | max_push = src_nritems / 2 + 1; | |
1987 | /* don't try to empty the node */ | |
d397712b | 1988 | if (max_push >= src_nritems) |
79f95c82 | 1989 | return 1; |
252c38f0 | 1990 | |
79f95c82 CM |
1991 | if (max_push < push_items) |
1992 | push_items = max_push; | |
1993 | ||
5f39d397 CM |
1994 | memmove_extent_buffer(dst, btrfs_node_key_ptr_offset(push_items), |
1995 | btrfs_node_key_ptr_offset(0), | |
1996 | (dst_nritems) * | |
1997 | sizeof(struct btrfs_key_ptr)); | |
d6025579 | 1998 | |
5f39d397 CM |
1999 | copy_extent_buffer(dst, src, |
2000 | btrfs_node_key_ptr_offset(0), | |
2001 | btrfs_node_key_ptr_offset(src_nritems - push_items), | |
d397712b | 2002 | push_items * sizeof(struct btrfs_key_ptr)); |
79f95c82 | 2003 | |
5f39d397 CM |
2004 | btrfs_set_header_nritems(src, src_nritems - push_items); |
2005 | btrfs_set_header_nritems(dst, dst_nritems + push_items); | |
79f95c82 | 2006 | |
5f39d397 CM |
2007 | btrfs_mark_buffer_dirty(src); |
2008 | btrfs_mark_buffer_dirty(dst); | |
31840ae1 ZY |
2009 | |
2010 | ret = btrfs_update_ref(trans, root, src, dst, 0, push_items); | |
2011 | BUG_ON(ret); | |
2012 | ||
aa5d6bed | 2013 | return ret; |
be0e5c09 CM |
2014 | } |
2015 | ||
97571fd0 CM |
2016 | /* |
2017 | * helper function to insert a new root level in the tree. | |
2018 | * A new node is allocated, and a single item is inserted to | |
2019 | * point to the existing root | |
aa5d6bed CM |
2020 | * |
2021 | * returns zero on success or < 0 on failure. | |
97571fd0 | 2022 | */ |
d397712b | 2023 | static noinline int insert_new_root(struct btrfs_trans_handle *trans, |
5f39d397 CM |
2024 | struct btrfs_root *root, |
2025 | struct btrfs_path *path, int level) | |
5c680ed6 | 2026 | { |
7bb86316 | 2027 | u64 lower_gen; |
5f39d397 CM |
2028 | struct extent_buffer *lower; |
2029 | struct extent_buffer *c; | |
925baedd | 2030 | struct extent_buffer *old; |
5f39d397 | 2031 | struct btrfs_disk_key lower_key; |
31840ae1 | 2032 | int ret; |
5c680ed6 CM |
2033 | |
2034 | BUG_ON(path->nodes[level]); | |
2035 | BUG_ON(path->nodes[level-1] != root->node); | |
2036 | ||
7bb86316 CM |
2037 | lower = path->nodes[level-1]; |
2038 | if (level == 1) | |
2039 | btrfs_item_key(lower, &lower_key, 0); | |
2040 | else | |
2041 | btrfs_node_key(lower, &lower_key, 0); | |
2042 | ||
31840ae1 ZY |
2043 | c = btrfs_alloc_free_block(trans, root, root->nodesize, 0, |
2044 | root->root_key.objectid, trans->transid, | |
ad3d81ba | 2045 | level, root->node->start, 0); |
5f39d397 CM |
2046 | if (IS_ERR(c)) |
2047 | return PTR_ERR(c); | |
925baedd | 2048 | |
5f39d397 CM |
2049 | memset_extent_buffer(c, 0, 0, root->nodesize); |
2050 | btrfs_set_header_nritems(c, 1); | |
2051 | btrfs_set_header_level(c, level); | |
db94535d | 2052 | btrfs_set_header_bytenr(c, c->start); |
5f39d397 CM |
2053 | btrfs_set_header_generation(c, trans->transid); |
2054 | btrfs_set_header_owner(c, root->root_key.objectid); | |
5f39d397 CM |
2055 | |
2056 | write_extent_buffer(c, root->fs_info->fsid, | |
2057 | (unsigned long)btrfs_header_fsid(c), | |
2058 | BTRFS_FSID_SIZE); | |
e17cade2 CM |
2059 | |
2060 | write_extent_buffer(c, root->fs_info->chunk_tree_uuid, | |
2061 | (unsigned long)btrfs_header_chunk_tree_uuid(c), | |
2062 | BTRFS_UUID_SIZE); | |
2063 | ||
5f39d397 | 2064 | btrfs_set_node_key(c, &lower_key, 0); |
db94535d | 2065 | btrfs_set_node_blockptr(c, 0, lower->start); |
7bb86316 | 2066 | lower_gen = btrfs_header_generation(lower); |
31840ae1 | 2067 | WARN_ON(lower_gen != trans->transid); |
7bb86316 CM |
2068 | |
2069 | btrfs_set_node_ptr_generation(c, 0, lower_gen); | |
d5719762 | 2070 | |
5f39d397 | 2071 | btrfs_mark_buffer_dirty(c); |
d5719762 | 2072 | |
925baedd CM |
2073 | spin_lock(&root->node_lock); |
2074 | old = root->node; | |
5f39d397 | 2075 | root->node = c; |
925baedd CM |
2076 | spin_unlock(&root->node_lock); |
2077 | ||
31840ae1 | 2078 | ret = btrfs_update_extent_ref(trans, root, lower->start, |
56bec294 | 2079 | lower->len, lower->start, c->start, |
31840ae1 | 2080 | root->root_key.objectid, |
3bb1a1bc | 2081 | trans->transid, level - 1); |
31840ae1 ZY |
2082 | BUG_ON(ret); |
2083 | ||
925baedd CM |
2084 | /* the super has an extra ref to root->node */ |
2085 | free_extent_buffer(old); | |
2086 | ||
0b86a832 | 2087 | add_root_to_dirty_list(root); |
5f39d397 CM |
2088 | extent_buffer_get(c); |
2089 | path->nodes[level] = c; | |
925baedd | 2090 | path->locks[level] = 1; |
5c680ed6 CM |
2091 | path->slots[level] = 0; |
2092 | return 0; | |
2093 | } | |
2094 | ||
74123bd7 CM |
2095 | /* |
2096 | * worker function to insert a single pointer in a node. | |
2097 | * the node should have enough room for the pointer already | |
97571fd0 | 2098 | * |
74123bd7 CM |
2099 | * slot and level indicate where you want the key to go, and |
2100 | * blocknr is the block the key points to. | |
aa5d6bed CM |
2101 | * |
2102 | * returns zero on success and < 0 on any error | |
74123bd7 | 2103 | */ |
e089f05c CM |
2104 | static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root |
2105 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
db94535d | 2106 | *key, u64 bytenr, int slot, int level) |
74123bd7 | 2107 | { |
5f39d397 | 2108 | struct extent_buffer *lower; |
74123bd7 | 2109 | int nritems; |
5c680ed6 CM |
2110 | |
2111 | BUG_ON(!path->nodes[level]); | |
5f39d397 CM |
2112 | lower = path->nodes[level]; |
2113 | nritems = btrfs_header_nritems(lower); | |
74123bd7 CM |
2114 | if (slot > nritems) |
2115 | BUG(); | |
123abc88 | 2116 | if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root)) |
74123bd7 CM |
2117 | BUG(); |
2118 | if (slot != nritems) { | |
5f39d397 CM |
2119 | memmove_extent_buffer(lower, |
2120 | btrfs_node_key_ptr_offset(slot + 1), | |
2121 | btrfs_node_key_ptr_offset(slot), | |
d6025579 | 2122 | (nritems - slot) * sizeof(struct btrfs_key_ptr)); |
74123bd7 | 2123 | } |
5f39d397 | 2124 | btrfs_set_node_key(lower, key, slot); |
db94535d | 2125 | btrfs_set_node_blockptr(lower, slot, bytenr); |
74493f7a CM |
2126 | WARN_ON(trans->transid == 0); |
2127 | btrfs_set_node_ptr_generation(lower, slot, trans->transid); | |
5f39d397 CM |
2128 | btrfs_set_header_nritems(lower, nritems + 1); |
2129 | btrfs_mark_buffer_dirty(lower); | |
74123bd7 CM |
2130 | return 0; |
2131 | } | |
2132 | ||
97571fd0 CM |
2133 | /* |
2134 | * split the node at the specified level in path in two. | |
2135 | * The path is corrected to point to the appropriate node after the split | |
2136 | * | |
2137 | * Before splitting this tries to make some room in the node by pushing | |
2138 | * left and right, if either one works, it returns right away. | |
aa5d6bed CM |
2139 | * |
2140 | * returns 0 on success and < 0 on failure | |
97571fd0 | 2141 | */ |
e02119d5 CM |
2142 | static noinline int split_node(struct btrfs_trans_handle *trans, |
2143 | struct btrfs_root *root, | |
2144 | struct btrfs_path *path, int level) | |
be0e5c09 | 2145 | { |
5f39d397 CM |
2146 | struct extent_buffer *c; |
2147 | struct extent_buffer *split; | |
2148 | struct btrfs_disk_key disk_key; | |
be0e5c09 | 2149 | int mid; |
5c680ed6 | 2150 | int ret; |
aa5d6bed | 2151 | int wret; |
7518a238 | 2152 | u32 c_nritems; |
eb60ceac | 2153 | |
5f39d397 | 2154 | c = path->nodes[level]; |
7bb86316 | 2155 | WARN_ON(btrfs_header_generation(c) != trans->transid); |
5f39d397 | 2156 | if (c == root->node) { |
5c680ed6 | 2157 | /* trying to split the root, lets make a new one */ |
e089f05c | 2158 | ret = insert_new_root(trans, root, path, level + 1); |
5c680ed6 CM |
2159 | if (ret) |
2160 | return ret; | |
e66f709b CM |
2161 | } else { |
2162 | ret = push_nodes_for_insert(trans, root, path, level); | |
5f39d397 CM |
2163 | c = path->nodes[level]; |
2164 | if (!ret && btrfs_header_nritems(c) < | |
c448acf0 | 2165 | BTRFS_NODEPTRS_PER_BLOCK(root) - 3) |
e66f709b | 2166 | return 0; |
54aa1f4d CM |
2167 | if (ret < 0) |
2168 | return ret; | |
be0e5c09 | 2169 | } |
e66f709b | 2170 | |
5f39d397 | 2171 | c_nritems = btrfs_header_nritems(c); |
7bb86316 | 2172 | |
925baedd | 2173 | split = btrfs_alloc_free_block(trans, root, root->nodesize, |
31840ae1 ZY |
2174 | path->nodes[level + 1]->start, |
2175 | root->root_key.objectid, | |
2176 | trans->transid, level, c->start, 0); | |
5f39d397 CM |
2177 | if (IS_ERR(split)) |
2178 | return PTR_ERR(split); | |
2179 | ||
2180 | btrfs_set_header_flags(split, btrfs_header_flags(c)); | |
2181 | btrfs_set_header_level(split, btrfs_header_level(c)); | |
db94535d | 2182 | btrfs_set_header_bytenr(split, split->start); |
5f39d397 CM |
2183 | btrfs_set_header_generation(split, trans->transid); |
2184 | btrfs_set_header_owner(split, root->root_key.objectid); | |
63b10fc4 | 2185 | btrfs_set_header_flags(split, 0); |
5f39d397 CM |
2186 | write_extent_buffer(split, root->fs_info->fsid, |
2187 | (unsigned long)btrfs_header_fsid(split), | |
2188 | BTRFS_FSID_SIZE); | |
e17cade2 CM |
2189 | write_extent_buffer(split, root->fs_info->chunk_tree_uuid, |
2190 | (unsigned long)btrfs_header_chunk_tree_uuid(split), | |
2191 | BTRFS_UUID_SIZE); | |
54aa1f4d | 2192 | |
7518a238 | 2193 | mid = (c_nritems + 1) / 2; |
5f39d397 CM |
2194 | |
2195 | copy_extent_buffer(split, c, | |
2196 | btrfs_node_key_ptr_offset(0), | |
2197 | btrfs_node_key_ptr_offset(mid), | |
2198 | (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); | |
2199 | btrfs_set_header_nritems(split, c_nritems - mid); | |
2200 | btrfs_set_header_nritems(c, mid); | |
aa5d6bed CM |
2201 | ret = 0; |
2202 | ||
5f39d397 CM |
2203 | btrfs_mark_buffer_dirty(c); |
2204 | btrfs_mark_buffer_dirty(split); | |
2205 | ||
2206 | btrfs_node_key(split, &disk_key, 0); | |
db94535d | 2207 | wret = insert_ptr(trans, root, path, &disk_key, split->start, |
5f39d397 | 2208 | path->slots[level + 1] + 1, |
123abc88 | 2209 | level + 1); |
aa5d6bed CM |
2210 | if (wret) |
2211 | ret = wret; | |
2212 | ||
31840ae1 ZY |
2213 | ret = btrfs_update_ref(trans, root, c, split, 0, c_nritems - mid); |
2214 | BUG_ON(ret); | |
2215 | ||
5de08d7d | 2216 | if (path->slots[level] >= mid) { |
5c680ed6 | 2217 | path->slots[level] -= mid; |
925baedd | 2218 | btrfs_tree_unlock(c); |
5f39d397 CM |
2219 | free_extent_buffer(c); |
2220 | path->nodes[level] = split; | |
5c680ed6 CM |
2221 | path->slots[level + 1] += 1; |
2222 | } else { | |
925baedd | 2223 | btrfs_tree_unlock(split); |
5f39d397 | 2224 | free_extent_buffer(split); |
be0e5c09 | 2225 | } |
aa5d6bed | 2226 | return ret; |
be0e5c09 CM |
2227 | } |
2228 | ||
74123bd7 CM |
2229 | /* |
2230 | * how many bytes are required to store the items in a leaf. start | |
2231 | * and nr indicate which items in the leaf to check. This totals up the | |
2232 | * space used both by the item structs and the item data | |
2233 | */ | |
5f39d397 | 2234 | static int leaf_space_used(struct extent_buffer *l, int start, int nr) |
be0e5c09 CM |
2235 | { |
2236 | int data_len; | |
5f39d397 | 2237 | int nritems = btrfs_header_nritems(l); |
d4dbff95 | 2238 | int end = min(nritems, start + nr) - 1; |
be0e5c09 CM |
2239 | |
2240 | if (!nr) | |
2241 | return 0; | |
5f39d397 CM |
2242 | data_len = btrfs_item_end_nr(l, start); |
2243 | data_len = data_len - btrfs_item_offset_nr(l, end); | |
0783fcfc | 2244 | data_len += sizeof(struct btrfs_item) * nr; |
d4dbff95 | 2245 | WARN_ON(data_len < 0); |
be0e5c09 CM |
2246 | return data_len; |
2247 | } | |
2248 | ||
d4dbff95 CM |
2249 | /* |
2250 | * The space between the end of the leaf items and | |
2251 | * the start of the leaf data. IOW, how much room | |
2252 | * the leaf has left for both items and data | |
2253 | */ | |
d397712b | 2254 | noinline int btrfs_leaf_free_space(struct btrfs_root *root, |
e02119d5 | 2255 | struct extent_buffer *leaf) |
d4dbff95 | 2256 | { |
5f39d397 CM |
2257 | int nritems = btrfs_header_nritems(leaf); |
2258 | int ret; | |
2259 | ret = BTRFS_LEAF_DATA_SIZE(root) - leaf_space_used(leaf, 0, nritems); | |
2260 | if (ret < 0) { | |
d397712b CM |
2261 | printk(KERN_CRIT "leaf free space ret %d, leaf data size %lu, " |
2262 | "used %d nritems %d\n", | |
ae2f5411 | 2263 | ret, (unsigned long) BTRFS_LEAF_DATA_SIZE(root), |
5f39d397 CM |
2264 | leaf_space_used(leaf, 0, nritems), nritems); |
2265 | } | |
2266 | return ret; | |
d4dbff95 CM |
2267 | } |
2268 | ||
00ec4c51 CM |
2269 | /* |
2270 | * push some data in the path leaf to the right, trying to free up at | |
2271 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
aa5d6bed CM |
2272 | * |
2273 | * returns 1 if the push failed because the other node didn't have enough | |
2274 | * room, 0 if everything worked out and < 0 if there were major errors. | |
00ec4c51 | 2275 | */ |
e089f05c | 2276 | static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root |
34a38218 CM |
2277 | *root, struct btrfs_path *path, int data_size, |
2278 | int empty) | |
00ec4c51 | 2279 | { |
5f39d397 CM |
2280 | struct extent_buffer *left = path->nodes[0]; |
2281 | struct extent_buffer *right; | |
2282 | struct extent_buffer *upper; | |
2283 | struct btrfs_disk_key disk_key; | |
00ec4c51 | 2284 | int slot; |
34a38218 | 2285 | u32 i; |
00ec4c51 CM |
2286 | int free_space; |
2287 | int push_space = 0; | |
2288 | int push_items = 0; | |
0783fcfc | 2289 | struct btrfs_item *item; |
7518a238 | 2290 | u32 left_nritems; |
34a38218 | 2291 | u32 nr; |
7518a238 | 2292 | u32 right_nritems; |
5f39d397 | 2293 | u32 data_end; |
db94535d | 2294 | u32 this_item_size; |
54aa1f4d | 2295 | int ret; |
00ec4c51 CM |
2296 | |
2297 | slot = path->slots[1]; | |
d397712b | 2298 | if (!path->nodes[1]) |
00ec4c51 | 2299 | return 1; |
d397712b | 2300 | |
00ec4c51 | 2301 | upper = path->nodes[1]; |
5f39d397 | 2302 | if (slot >= btrfs_header_nritems(upper) - 1) |
00ec4c51 | 2303 | return 1; |
5f39d397 | 2304 | |
b9447ef8 | 2305 | btrfs_assert_tree_locked(path->nodes[1]); |
a2135011 | 2306 | |
ca7a79ad | 2307 | right = read_node_slot(root, upper, slot + 1); |
925baedd | 2308 | btrfs_tree_lock(right); |
b4ce94de CM |
2309 | btrfs_set_lock_blocking(right); |
2310 | ||
123abc88 | 2311 | free_space = btrfs_leaf_free_space(root, right); |
87b29b20 | 2312 | if (free_space < data_size) |
925baedd | 2313 | goto out_unlock; |
5f39d397 | 2314 | |
02217ed2 | 2315 | /* cow and double check */ |
5f39d397 | 2316 | ret = btrfs_cow_block(trans, root, right, upper, |
9fa8cfe7 | 2317 | slot + 1, &right); |
925baedd CM |
2318 | if (ret) |
2319 | goto out_unlock; | |
2320 | ||
123abc88 | 2321 | free_space = btrfs_leaf_free_space(root, right); |
87b29b20 | 2322 | if (free_space < data_size) |
925baedd | 2323 | goto out_unlock; |
02217ed2 | 2324 | |
5f39d397 | 2325 | left_nritems = btrfs_header_nritems(left); |
925baedd CM |
2326 | if (left_nritems == 0) |
2327 | goto out_unlock; | |
5f39d397 | 2328 | |
34a38218 CM |
2329 | if (empty) |
2330 | nr = 0; | |
2331 | else | |
2332 | nr = 1; | |
2333 | ||
31840ae1 | 2334 | if (path->slots[0] >= left_nritems) |
87b29b20 | 2335 | push_space += data_size; |
31840ae1 | 2336 | |
34a38218 CM |
2337 | i = left_nritems - 1; |
2338 | while (i >= nr) { | |
5f39d397 | 2339 | item = btrfs_item_nr(left, i); |
db94535d | 2340 | |
31840ae1 ZY |
2341 | if (!empty && push_items > 0) { |
2342 | if (path->slots[0] > i) | |
2343 | break; | |
2344 | if (path->slots[0] == i) { | |
2345 | int space = btrfs_leaf_free_space(root, left); | |
2346 | if (space + push_space * 2 > free_space) | |
2347 | break; | |
2348 | } | |
2349 | } | |
2350 | ||
00ec4c51 | 2351 | if (path->slots[0] == i) |
87b29b20 | 2352 | push_space += data_size; |
db94535d CM |
2353 | |
2354 | if (!left->map_token) { | |
2355 | map_extent_buffer(left, (unsigned long)item, | |
2356 | sizeof(struct btrfs_item), | |
2357 | &left->map_token, &left->kaddr, | |
2358 | &left->map_start, &left->map_len, | |
2359 | KM_USER1); | |
2360 | } | |
2361 | ||
2362 | this_item_size = btrfs_item_size(left, item); | |
2363 | if (this_item_size + sizeof(*item) + push_space > free_space) | |
00ec4c51 | 2364 | break; |
31840ae1 | 2365 | |
00ec4c51 | 2366 | push_items++; |
db94535d | 2367 | push_space += this_item_size + sizeof(*item); |
34a38218 CM |
2368 | if (i == 0) |
2369 | break; | |
2370 | i--; | |
db94535d CM |
2371 | } |
2372 | if (left->map_token) { | |
2373 | unmap_extent_buffer(left, left->map_token, KM_USER1); | |
2374 | left->map_token = NULL; | |
00ec4c51 | 2375 | } |
5f39d397 | 2376 | |
925baedd CM |
2377 | if (push_items == 0) |
2378 | goto out_unlock; | |
5f39d397 | 2379 | |
34a38218 | 2380 | if (!empty && push_items == left_nritems) |
a429e513 | 2381 | WARN_ON(1); |
5f39d397 | 2382 | |
00ec4c51 | 2383 | /* push left to right */ |
5f39d397 | 2384 | right_nritems = btrfs_header_nritems(right); |
34a38218 | 2385 | |
5f39d397 | 2386 | push_space = btrfs_item_end_nr(left, left_nritems - push_items); |
123abc88 | 2387 | push_space -= leaf_data_end(root, left); |
5f39d397 | 2388 | |
00ec4c51 | 2389 | /* make room in the right data area */ |
5f39d397 CM |
2390 | data_end = leaf_data_end(root, right); |
2391 | memmove_extent_buffer(right, | |
2392 | btrfs_leaf_data(right) + data_end - push_space, | |
2393 | btrfs_leaf_data(right) + data_end, | |
2394 | BTRFS_LEAF_DATA_SIZE(root) - data_end); | |
2395 | ||
00ec4c51 | 2396 | /* copy from the left data area */ |
5f39d397 | 2397 | copy_extent_buffer(right, left, btrfs_leaf_data(right) + |
d6025579 CM |
2398 | BTRFS_LEAF_DATA_SIZE(root) - push_space, |
2399 | btrfs_leaf_data(left) + leaf_data_end(root, left), | |
2400 | push_space); | |
5f39d397 CM |
2401 | |
2402 | memmove_extent_buffer(right, btrfs_item_nr_offset(push_items), | |
2403 | btrfs_item_nr_offset(0), | |
2404 | right_nritems * sizeof(struct btrfs_item)); | |
2405 | ||
00ec4c51 | 2406 | /* copy the items from left to right */ |
5f39d397 CM |
2407 | copy_extent_buffer(right, left, btrfs_item_nr_offset(0), |
2408 | btrfs_item_nr_offset(left_nritems - push_items), | |
2409 | push_items * sizeof(struct btrfs_item)); | |
00ec4c51 CM |
2410 | |
2411 | /* update the item pointers */ | |
7518a238 | 2412 | right_nritems += push_items; |
5f39d397 | 2413 | btrfs_set_header_nritems(right, right_nritems); |
123abc88 | 2414 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
7518a238 | 2415 | for (i = 0; i < right_nritems; i++) { |
5f39d397 | 2416 | item = btrfs_item_nr(right, i); |
db94535d CM |
2417 | if (!right->map_token) { |
2418 | map_extent_buffer(right, (unsigned long)item, | |
2419 | sizeof(struct btrfs_item), | |
2420 | &right->map_token, &right->kaddr, | |
2421 | &right->map_start, &right->map_len, | |
2422 | KM_USER1); | |
2423 | } | |
2424 | push_space -= btrfs_item_size(right, item); | |
2425 | btrfs_set_item_offset(right, item, push_space); | |
2426 | } | |
2427 | ||
2428 | if (right->map_token) { | |
2429 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
2430 | right->map_token = NULL; | |
00ec4c51 | 2431 | } |
7518a238 | 2432 | left_nritems -= push_items; |
5f39d397 | 2433 | btrfs_set_header_nritems(left, left_nritems); |
00ec4c51 | 2434 | |
34a38218 CM |
2435 | if (left_nritems) |
2436 | btrfs_mark_buffer_dirty(left); | |
5f39d397 | 2437 | btrfs_mark_buffer_dirty(right); |
a429e513 | 2438 | |
31840ae1 ZY |
2439 | ret = btrfs_update_ref(trans, root, left, right, 0, push_items); |
2440 | BUG_ON(ret); | |
2441 | ||
5f39d397 CM |
2442 | btrfs_item_key(right, &disk_key, 0); |
2443 | btrfs_set_node_key(upper, &disk_key, slot + 1); | |
d6025579 | 2444 | btrfs_mark_buffer_dirty(upper); |
02217ed2 | 2445 | |
00ec4c51 | 2446 | /* then fixup the leaf pointer in the path */ |
7518a238 CM |
2447 | if (path->slots[0] >= left_nritems) { |
2448 | path->slots[0] -= left_nritems; | |
925baedd CM |
2449 | if (btrfs_header_nritems(path->nodes[0]) == 0) |
2450 | clean_tree_block(trans, root, path->nodes[0]); | |
2451 | btrfs_tree_unlock(path->nodes[0]); | |
5f39d397 CM |
2452 | free_extent_buffer(path->nodes[0]); |
2453 | path->nodes[0] = right; | |
00ec4c51 CM |
2454 | path->slots[1] += 1; |
2455 | } else { | |
925baedd | 2456 | btrfs_tree_unlock(right); |
5f39d397 | 2457 | free_extent_buffer(right); |
00ec4c51 CM |
2458 | } |
2459 | return 0; | |
925baedd CM |
2460 | |
2461 | out_unlock: | |
2462 | btrfs_tree_unlock(right); | |
2463 | free_extent_buffer(right); | |
2464 | return 1; | |
00ec4c51 | 2465 | } |
925baedd | 2466 | |
74123bd7 CM |
2467 | /* |
2468 | * push some data in the path leaf to the left, trying to free up at | |
2469 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
2470 | */ | |
e089f05c | 2471 | static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root |
34a38218 CM |
2472 | *root, struct btrfs_path *path, int data_size, |
2473 | int empty) | |
be0e5c09 | 2474 | { |
5f39d397 CM |
2475 | struct btrfs_disk_key disk_key; |
2476 | struct extent_buffer *right = path->nodes[0]; | |
2477 | struct extent_buffer *left; | |
be0e5c09 CM |
2478 | int slot; |
2479 | int i; | |
2480 | int free_space; | |
2481 | int push_space = 0; | |
2482 | int push_items = 0; | |
0783fcfc | 2483 | struct btrfs_item *item; |
7518a238 | 2484 | u32 old_left_nritems; |
5f39d397 | 2485 | u32 right_nritems; |
34a38218 | 2486 | u32 nr; |
aa5d6bed CM |
2487 | int ret = 0; |
2488 | int wret; | |
db94535d CM |
2489 | u32 this_item_size; |
2490 | u32 old_left_item_size; | |
be0e5c09 CM |
2491 | |
2492 | slot = path->slots[1]; | |
5f39d397 | 2493 | if (slot == 0) |
be0e5c09 | 2494 | return 1; |
5f39d397 | 2495 | if (!path->nodes[1]) |
be0e5c09 | 2496 | return 1; |
5f39d397 | 2497 | |
3685f791 | 2498 | right_nritems = btrfs_header_nritems(right); |
d397712b | 2499 | if (right_nritems == 0) |
3685f791 | 2500 | return 1; |
3685f791 | 2501 | |
b9447ef8 | 2502 | btrfs_assert_tree_locked(path->nodes[1]); |
a2135011 | 2503 | |
ca7a79ad | 2504 | left = read_node_slot(root, path->nodes[1], slot - 1); |
925baedd | 2505 | btrfs_tree_lock(left); |
b4ce94de CM |
2506 | btrfs_set_lock_blocking(left); |
2507 | ||
123abc88 | 2508 | free_space = btrfs_leaf_free_space(root, left); |
87b29b20 | 2509 | if (free_space < data_size) { |
925baedd CM |
2510 | ret = 1; |
2511 | goto out; | |
be0e5c09 | 2512 | } |
02217ed2 CM |
2513 | |
2514 | /* cow and double check */ | |
5f39d397 | 2515 | ret = btrfs_cow_block(trans, root, left, |
9fa8cfe7 | 2516 | path->nodes[1], slot - 1, &left); |
54aa1f4d CM |
2517 | if (ret) { |
2518 | /* we hit -ENOSPC, but it isn't fatal here */ | |
925baedd CM |
2519 | ret = 1; |
2520 | goto out; | |
54aa1f4d | 2521 | } |
3685f791 | 2522 | |
123abc88 | 2523 | free_space = btrfs_leaf_free_space(root, left); |
87b29b20 | 2524 | if (free_space < data_size) { |
925baedd CM |
2525 | ret = 1; |
2526 | goto out; | |
02217ed2 CM |
2527 | } |
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 | |
31840ae1 ZY |
2663 | ret = btrfs_update_ref(trans, root, right, left, |
2664 | old_left_nritems, push_items); | |
2665 | BUG_ON(ret); | |
2666 | ||
5f39d397 CM |
2667 | btrfs_item_key(right, &disk_key, 0); |
2668 | wret = fixup_low_keys(trans, root, path, &disk_key, 1); | |
aa5d6bed CM |
2669 | if (wret) |
2670 | ret = wret; | |
be0e5c09 CM |
2671 | |
2672 | /* then fixup the leaf pointer in the path */ | |
2673 | if (path->slots[0] < push_items) { | |
2674 | path->slots[0] += old_left_nritems; | |
925baedd CM |
2675 | if (btrfs_header_nritems(path->nodes[0]) == 0) |
2676 | clean_tree_block(trans, root, path->nodes[0]); | |
2677 | btrfs_tree_unlock(path->nodes[0]); | |
5f39d397 CM |
2678 | free_extent_buffer(path->nodes[0]); |
2679 | path->nodes[0] = left; | |
be0e5c09 CM |
2680 | path->slots[1] -= 1; |
2681 | } else { | |
925baedd | 2682 | btrfs_tree_unlock(left); |
5f39d397 | 2683 | free_extent_buffer(left); |
be0e5c09 CM |
2684 | path->slots[0] -= push_items; |
2685 | } | |
eb60ceac | 2686 | BUG_ON(path->slots[0] < 0); |
aa5d6bed | 2687 | return ret; |
925baedd CM |
2688 | out: |
2689 | btrfs_tree_unlock(left); | |
2690 | free_extent_buffer(left); | |
2691 | return ret; | |
be0e5c09 CM |
2692 | } |
2693 | ||
74123bd7 CM |
2694 | /* |
2695 | * split the path's leaf in two, making sure there is at least data_size | |
2696 | * available for the resulting leaf level of the path. | |
aa5d6bed CM |
2697 | * |
2698 | * returns 0 if all went well and < 0 on failure. | |
74123bd7 | 2699 | */ |
e02119d5 CM |
2700 | static noinline int split_leaf(struct btrfs_trans_handle *trans, |
2701 | struct btrfs_root *root, | |
2702 | struct btrfs_key *ins_key, | |
2703 | struct btrfs_path *path, int data_size, | |
2704 | int extend) | |
be0e5c09 | 2705 | { |
5f39d397 | 2706 | struct extent_buffer *l; |
7518a238 | 2707 | u32 nritems; |
eb60ceac CM |
2708 | int mid; |
2709 | int slot; | |
5f39d397 | 2710 | struct extent_buffer *right; |
be0e5c09 CM |
2711 | int data_copy_size; |
2712 | int rt_data_off; | |
2713 | int i; | |
d4dbff95 | 2714 | int ret = 0; |
aa5d6bed | 2715 | int wret; |
cc0c5538 CM |
2716 | int double_split; |
2717 | int num_doubles = 0; | |
d4dbff95 | 2718 | struct btrfs_disk_key disk_key; |
aa5d6bed | 2719 | |
40689478 | 2720 | /* first try to make some room by pushing left and right */ |
459931ec | 2721 | if (data_size && ins_key->type != BTRFS_DIR_ITEM_KEY) { |
34a38218 | 2722 | wret = push_leaf_right(trans, root, path, data_size, 0); |
d397712b | 2723 | if (wret < 0) |
eaee50e8 | 2724 | return wret; |
3685f791 | 2725 | if (wret) { |
34a38218 | 2726 | wret = push_leaf_left(trans, root, path, data_size, 0); |
3685f791 CM |
2727 | if (wret < 0) |
2728 | return wret; | |
2729 | } | |
2730 | l = path->nodes[0]; | |
aa5d6bed | 2731 | |
3685f791 | 2732 | /* did the pushes work? */ |
87b29b20 | 2733 | if (btrfs_leaf_free_space(root, l) >= data_size) |
3685f791 | 2734 | return 0; |
3326d1b0 | 2735 | } |
aa5d6bed | 2736 | |
5c680ed6 | 2737 | if (!path->nodes[1]) { |
e089f05c | 2738 | ret = insert_new_root(trans, root, path, 1); |
5c680ed6 CM |
2739 | if (ret) |
2740 | return ret; | |
2741 | } | |
cc0c5538 CM |
2742 | again: |
2743 | double_split = 0; | |
2744 | l = path->nodes[0]; | |
eb60ceac | 2745 | slot = path->slots[0]; |
5f39d397 | 2746 | nritems = btrfs_header_nritems(l); |
d397712b | 2747 | mid = (nritems + 1) / 2; |
54aa1f4d | 2748 | |
925baedd | 2749 | right = btrfs_alloc_free_block(trans, root, root->leafsize, |
31840ae1 ZY |
2750 | path->nodes[1]->start, |
2751 | root->root_key.objectid, | |
2752 | trans->transid, 0, l->start, 0); | |
cea9e445 CM |
2753 | if (IS_ERR(right)) { |
2754 | BUG_ON(1); | |
5f39d397 | 2755 | return PTR_ERR(right); |
cea9e445 | 2756 | } |
5f39d397 CM |
2757 | |
2758 | memset_extent_buffer(right, 0, 0, sizeof(struct btrfs_header)); | |
db94535d | 2759 | btrfs_set_header_bytenr(right, right->start); |
5f39d397 CM |
2760 | btrfs_set_header_generation(right, trans->transid); |
2761 | btrfs_set_header_owner(right, root->root_key.objectid); | |
2762 | btrfs_set_header_level(right, 0); | |
2763 | write_extent_buffer(right, root->fs_info->fsid, | |
2764 | (unsigned long)btrfs_header_fsid(right), | |
2765 | BTRFS_FSID_SIZE); | |
e17cade2 CM |
2766 | |
2767 | write_extent_buffer(right, root->fs_info->chunk_tree_uuid, | |
2768 | (unsigned long)btrfs_header_chunk_tree_uuid(right), | |
2769 | BTRFS_UUID_SIZE); | |
d4dbff95 CM |
2770 | if (mid <= slot) { |
2771 | if (nritems == 1 || | |
87b29b20 | 2772 | leaf_space_used(l, mid, nritems - mid) + data_size > |
d4dbff95 CM |
2773 | BTRFS_LEAF_DATA_SIZE(root)) { |
2774 | if (slot >= nritems) { | |
2775 | btrfs_cpu_key_to_disk(&disk_key, ins_key); | |
5f39d397 | 2776 | btrfs_set_header_nritems(right, 0); |
d4dbff95 | 2777 | wret = insert_ptr(trans, root, path, |
db94535d | 2778 | &disk_key, right->start, |
d4dbff95 CM |
2779 | path->slots[1] + 1, 1); |
2780 | if (wret) | |
2781 | ret = wret; | |
925baedd CM |
2782 | |
2783 | btrfs_tree_unlock(path->nodes[0]); | |
5f39d397 CM |
2784 | free_extent_buffer(path->nodes[0]); |
2785 | path->nodes[0] = right; | |
d4dbff95 CM |
2786 | path->slots[0] = 0; |
2787 | path->slots[1] += 1; | |
0ef8b242 | 2788 | btrfs_mark_buffer_dirty(right); |
d4dbff95 CM |
2789 | return ret; |
2790 | } | |
2791 | mid = slot; | |
3326d1b0 CM |
2792 | if (mid != nritems && |
2793 | leaf_space_used(l, mid, nritems - mid) + | |
87b29b20 | 2794 | data_size > BTRFS_LEAF_DATA_SIZE(root)) { |
3326d1b0 CM |
2795 | double_split = 1; |
2796 | } | |
d4dbff95 CM |
2797 | } |
2798 | } else { | |
87b29b20 | 2799 | if (leaf_space_used(l, 0, mid) + data_size > |
d4dbff95 | 2800 | BTRFS_LEAF_DATA_SIZE(root)) { |
459931ec | 2801 | if (!extend && data_size && slot == 0) { |
d4dbff95 | 2802 | btrfs_cpu_key_to_disk(&disk_key, ins_key); |
5f39d397 | 2803 | btrfs_set_header_nritems(right, 0); |
d4dbff95 CM |
2804 | wret = insert_ptr(trans, root, path, |
2805 | &disk_key, | |
db94535d | 2806 | right->start, |
098f59c2 | 2807 | path->slots[1], 1); |
d4dbff95 CM |
2808 | if (wret) |
2809 | ret = wret; | |
925baedd | 2810 | btrfs_tree_unlock(path->nodes[0]); |
5f39d397 CM |
2811 | free_extent_buffer(path->nodes[0]); |
2812 | path->nodes[0] = right; | |
d4dbff95 | 2813 | path->slots[0] = 0; |
a429e513 CM |
2814 | if (path->slots[1] == 0) { |
2815 | wret = fixup_low_keys(trans, root, | |
d397712b | 2816 | path, &disk_key, 1); |
a429e513 CM |
2817 | if (wret) |
2818 | ret = wret; | |
2819 | } | |
0ef8b242 | 2820 | btrfs_mark_buffer_dirty(right); |
d4dbff95 | 2821 | return ret; |
459931ec | 2822 | } else if ((extend || !data_size) && slot == 0) { |
cc0c5538 CM |
2823 | mid = 1; |
2824 | } else { | |
2825 | mid = slot; | |
2826 | if (mid != nritems && | |
2827 | leaf_space_used(l, mid, nritems - mid) + | |
87b29b20 | 2828 | data_size > BTRFS_LEAF_DATA_SIZE(root)) { |
cc0c5538 CM |
2829 | double_split = 1; |
2830 | } | |
5ee78ac7 | 2831 | } |
d4dbff95 CM |
2832 | } |
2833 | } | |
5f39d397 CM |
2834 | nritems = nritems - mid; |
2835 | btrfs_set_header_nritems(right, nritems); | |
2836 | data_copy_size = btrfs_item_end_nr(l, mid) - leaf_data_end(root, l); | |
2837 | ||
2838 | copy_extent_buffer(right, l, btrfs_item_nr_offset(0), | |
2839 | btrfs_item_nr_offset(mid), | |
2840 | nritems * sizeof(struct btrfs_item)); | |
2841 | ||
2842 | copy_extent_buffer(right, l, | |
d6025579 CM |
2843 | btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - |
2844 | data_copy_size, btrfs_leaf_data(l) + | |
2845 | leaf_data_end(root, l), data_copy_size); | |
5f39d397 | 2846 | |
123abc88 | 2847 | rt_data_off = BTRFS_LEAF_DATA_SIZE(root) - |
5f39d397 | 2848 | btrfs_item_end_nr(l, mid); |
74123bd7 | 2849 | |
5f39d397 CM |
2850 | for (i = 0; i < nritems; i++) { |
2851 | struct btrfs_item *item = btrfs_item_nr(right, i); | |
db94535d CM |
2852 | u32 ioff; |
2853 | ||
2854 | if (!right->map_token) { | |
2855 | map_extent_buffer(right, (unsigned long)item, | |
2856 | sizeof(struct btrfs_item), | |
2857 | &right->map_token, &right->kaddr, | |
2858 | &right->map_start, &right->map_len, | |
2859 | KM_USER1); | |
2860 | } | |
2861 | ||
2862 | ioff = btrfs_item_offset(right, item); | |
5f39d397 | 2863 | btrfs_set_item_offset(right, item, ioff + rt_data_off); |
0783fcfc | 2864 | } |
74123bd7 | 2865 | |
db94535d CM |
2866 | if (right->map_token) { |
2867 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
2868 | right->map_token = NULL; | |
2869 | } | |
2870 | ||
5f39d397 | 2871 | btrfs_set_header_nritems(l, mid); |
aa5d6bed | 2872 | ret = 0; |
5f39d397 | 2873 | btrfs_item_key(right, &disk_key, 0); |
db94535d CM |
2874 | wret = insert_ptr(trans, root, path, &disk_key, right->start, |
2875 | path->slots[1] + 1, 1); | |
aa5d6bed CM |
2876 | if (wret) |
2877 | ret = wret; | |
5f39d397 CM |
2878 | |
2879 | btrfs_mark_buffer_dirty(right); | |
2880 | btrfs_mark_buffer_dirty(l); | |
eb60ceac | 2881 | BUG_ON(path->slots[0] != slot); |
5f39d397 | 2882 | |
31840ae1 ZY |
2883 | ret = btrfs_update_ref(trans, root, l, right, 0, nritems); |
2884 | BUG_ON(ret); | |
2885 | ||
be0e5c09 | 2886 | if (mid <= slot) { |
925baedd | 2887 | btrfs_tree_unlock(path->nodes[0]); |
5f39d397 CM |
2888 | free_extent_buffer(path->nodes[0]); |
2889 | path->nodes[0] = right; | |
be0e5c09 CM |
2890 | path->slots[0] -= mid; |
2891 | path->slots[1] += 1; | |
925baedd CM |
2892 | } else { |
2893 | btrfs_tree_unlock(right); | |
5f39d397 | 2894 | free_extent_buffer(right); |
925baedd | 2895 | } |
5f39d397 | 2896 | |
eb60ceac | 2897 | BUG_ON(path->slots[0] < 0); |
d4dbff95 | 2898 | |
cc0c5538 CM |
2899 | if (double_split) { |
2900 | BUG_ON(num_doubles != 0); | |
2901 | num_doubles++; | |
2902 | goto again; | |
a429e513 | 2903 | } |
be0e5c09 CM |
2904 | return ret; |
2905 | } | |
2906 | ||
459931ec CM |
2907 | /* |
2908 | * This function splits a single item into two items, | |
2909 | * giving 'new_key' to the new item and splitting the | |
2910 | * old one at split_offset (from the start of the item). | |
2911 | * | |
2912 | * The path may be released by this operation. After | |
2913 | * the split, the path is pointing to the old item. The | |
2914 | * new item is going to be in the same node as the old one. | |
2915 | * | |
2916 | * Note, the item being split must be smaller enough to live alone on | |
2917 | * a tree block with room for one extra struct btrfs_item | |
2918 | * | |
2919 | * This allows us to split the item in place, keeping a lock on the | |
2920 | * leaf the entire time. | |
2921 | */ | |
2922 | int btrfs_split_item(struct btrfs_trans_handle *trans, | |
2923 | struct btrfs_root *root, | |
2924 | struct btrfs_path *path, | |
2925 | struct btrfs_key *new_key, | |
2926 | unsigned long split_offset) | |
2927 | { | |
2928 | u32 item_size; | |
2929 | struct extent_buffer *leaf; | |
2930 | struct btrfs_key orig_key; | |
2931 | struct btrfs_item *item; | |
2932 | struct btrfs_item *new_item; | |
2933 | int ret = 0; | |
2934 | int slot; | |
2935 | u32 nritems; | |
2936 | u32 orig_offset; | |
2937 | struct btrfs_disk_key disk_key; | |
2938 | char *buf; | |
2939 | ||
2940 | leaf = path->nodes[0]; | |
2941 | btrfs_item_key_to_cpu(leaf, &orig_key, path->slots[0]); | |
2942 | if (btrfs_leaf_free_space(root, leaf) >= sizeof(struct btrfs_item)) | |
2943 | goto split; | |
2944 | ||
2945 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); | |
2946 | btrfs_release_path(root, path); | |
2947 | ||
2948 | path->search_for_split = 1; | |
2949 | path->keep_locks = 1; | |
2950 | ||
2951 | ret = btrfs_search_slot(trans, root, &orig_key, path, 0, 1); | |
2952 | path->search_for_split = 0; | |
2953 | ||
2954 | /* if our item isn't there or got smaller, return now */ | |
2955 | if (ret != 0 || item_size != btrfs_item_size_nr(path->nodes[0], | |
2956 | path->slots[0])) { | |
2957 | path->keep_locks = 0; | |
2958 | return -EAGAIN; | |
2959 | } | |
2960 | ||
87b29b20 YZ |
2961 | ret = split_leaf(trans, root, &orig_key, path, |
2962 | sizeof(struct btrfs_item), 1); | |
459931ec CM |
2963 | path->keep_locks = 0; |
2964 | BUG_ON(ret); | |
2965 | ||
b4ce94de CM |
2966 | /* |
2967 | * make sure any changes to the path from split_leaf leave it | |
2968 | * in a blocking state | |
2969 | */ | |
2970 | btrfs_set_path_blocking(path); | |
2971 | ||
459931ec | 2972 | leaf = path->nodes[0]; |
42dc7bab | 2973 | BUG_ON(btrfs_leaf_free_space(root, leaf) < sizeof(struct btrfs_item)); |
459931ec CM |
2974 | |
2975 | split: | |
2976 | item = btrfs_item_nr(leaf, path->slots[0]); | |
2977 | orig_offset = btrfs_item_offset(leaf, item); | |
2978 | item_size = btrfs_item_size(leaf, item); | |
2979 | ||
2980 | ||
2981 | buf = kmalloc(item_size, GFP_NOFS); | |
2982 | read_extent_buffer(leaf, buf, btrfs_item_ptr_offset(leaf, | |
2983 | path->slots[0]), item_size); | |
2984 | slot = path->slots[0] + 1; | |
2985 | leaf = path->nodes[0]; | |
2986 | ||
2987 | nritems = btrfs_header_nritems(leaf); | |
2988 | ||
2989 | if (slot != nritems) { | |
2990 | /* shift the items */ | |
2991 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + 1), | |
2992 | btrfs_item_nr_offset(slot), | |
2993 | (nritems - slot) * sizeof(struct btrfs_item)); | |
2994 | ||
2995 | } | |
2996 | ||
2997 | btrfs_cpu_key_to_disk(&disk_key, new_key); | |
2998 | btrfs_set_item_key(leaf, &disk_key, slot); | |
2999 | ||
3000 | new_item = btrfs_item_nr(leaf, slot); | |
3001 | ||
3002 | btrfs_set_item_offset(leaf, new_item, orig_offset); | |
3003 | btrfs_set_item_size(leaf, new_item, item_size - split_offset); | |
3004 | ||
3005 | btrfs_set_item_offset(leaf, item, | |
3006 | orig_offset + item_size - split_offset); | |
3007 | btrfs_set_item_size(leaf, item, split_offset); | |
3008 | ||
3009 | btrfs_set_header_nritems(leaf, nritems + 1); | |
3010 | ||
3011 | /* write the data for the start of the original item */ | |
3012 | write_extent_buffer(leaf, buf, | |
3013 | btrfs_item_ptr_offset(leaf, path->slots[0]), | |
3014 | split_offset); | |
3015 | ||
3016 | /* write the data for the new item */ | |
3017 | write_extent_buffer(leaf, buf + split_offset, | |
3018 | btrfs_item_ptr_offset(leaf, slot), | |
3019 | item_size - split_offset); | |
3020 | btrfs_mark_buffer_dirty(leaf); | |
3021 | ||
3022 | ret = 0; | |
3023 | if (btrfs_leaf_free_space(root, leaf) < 0) { | |
3024 | btrfs_print_leaf(root, leaf); | |
3025 | BUG(); | |
3026 | } | |
3027 | kfree(buf); | |
3028 | return ret; | |
3029 | } | |
3030 | ||
d352ac68 CM |
3031 | /* |
3032 | * make the item pointed to by the path smaller. new_size indicates | |
3033 | * how small to make it, and from_end tells us if we just chop bytes | |
3034 | * off the end of the item or if we shift the item to chop bytes off | |
3035 | * the front. | |
3036 | */ | |
b18c6685 CM |
3037 | int btrfs_truncate_item(struct btrfs_trans_handle *trans, |
3038 | struct btrfs_root *root, | |
3039 | struct btrfs_path *path, | |
179e29e4 | 3040 | u32 new_size, int from_end) |
b18c6685 CM |
3041 | { |
3042 | int ret = 0; | |
3043 | int slot; | |
3044 | int slot_orig; | |
5f39d397 CM |
3045 | struct extent_buffer *leaf; |
3046 | struct btrfs_item *item; | |
b18c6685 CM |
3047 | u32 nritems; |
3048 | unsigned int data_end; | |
3049 | unsigned int old_data_start; | |
3050 | unsigned int old_size; | |
3051 | unsigned int size_diff; | |
3052 | int i; | |
3053 | ||
3054 | slot_orig = path->slots[0]; | |
5f39d397 | 3055 | leaf = path->nodes[0]; |
179e29e4 CM |
3056 | slot = path->slots[0]; |
3057 | ||
3058 | old_size = btrfs_item_size_nr(leaf, slot); | |
3059 | if (old_size == new_size) | |
3060 | return 0; | |
b18c6685 | 3061 | |
5f39d397 | 3062 | nritems = btrfs_header_nritems(leaf); |
b18c6685 CM |
3063 | data_end = leaf_data_end(root, leaf); |
3064 | ||
5f39d397 | 3065 | old_data_start = btrfs_item_offset_nr(leaf, slot); |
179e29e4 | 3066 | |
b18c6685 CM |
3067 | size_diff = old_size - new_size; |
3068 | ||
3069 | BUG_ON(slot < 0); | |
3070 | BUG_ON(slot >= nritems); | |
3071 | ||
3072 | /* | |
3073 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
3074 | */ | |
3075 | /* first correct the data pointers */ | |
3076 | for (i = slot; i < nritems; i++) { | |
5f39d397 CM |
3077 | u32 ioff; |
3078 | item = btrfs_item_nr(leaf, i); | |
db94535d CM |
3079 | |
3080 | if (!leaf->map_token) { | |
3081 | map_extent_buffer(leaf, (unsigned long)item, | |
3082 | sizeof(struct btrfs_item), | |
3083 | &leaf->map_token, &leaf->kaddr, | |
3084 | &leaf->map_start, &leaf->map_len, | |
3085 | KM_USER1); | |
3086 | } | |
3087 | ||
5f39d397 CM |
3088 | ioff = btrfs_item_offset(leaf, item); |
3089 | btrfs_set_item_offset(leaf, item, ioff + size_diff); | |
b18c6685 | 3090 | } |
db94535d CM |
3091 | |
3092 | if (leaf->map_token) { | |
3093 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
3094 | leaf->map_token = NULL; | |
3095 | } | |
3096 | ||
b18c6685 | 3097 | /* shift the data */ |
179e29e4 CM |
3098 | if (from_end) { |
3099 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
3100 | data_end + size_diff, btrfs_leaf_data(leaf) + | |
3101 | data_end, old_data_start + new_size - data_end); | |
3102 | } else { | |
3103 | struct btrfs_disk_key disk_key; | |
3104 | u64 offset; | |
3105 | ||
3106 | btrfs_item_key(leaf, &disk_key, slot); | |
3107 | ||
3108 | if (btrfs_disk_key_type(&disk_key) == BTRFS_EXTENT_DATA_KEY) { | |
3109 | unsigned long ptr; | |
3110 | struct btrfs_file_extent_item *fi; | |
3111 | ||
3112 | fi = btrfs_item_ptr(leaf, slot, | |
3113 | struct btrfs_file_extent_item); | |
3114 | fi = (struct btrfs_file_extent_item *)( | |
3115 | (unsigned long)fi - size_diff); | |
3116 | ||
3117 | if (btrfs_file_extent_type(leaf, fi) == | |
3118 | BTRFS_FILE_EXTENT_INLINE) { | |
3119 | ptr = btrfs_item_ptr_offset(leaf, slot); | |
3120 | memmove_extent_buffer(leaf, ptr, | |
d397712b CM |
3121 | (unsigned long)fi, |
3122 | offsetof(struct btrfs_file_extent_item, | |
179e29e4 CM |
3123 | disk_bytenr)); |
3124 | } | |
3125 | } | |
3126 | ||
3127 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
3128 | data_end + size_diff, btrfs_leaf_data(leaf) + | |
3129 | data_end, old_data_start - data_end); | |
3130 | ||
3131 | offset = btrfs_disk_key_offset(&disk_key); | |
3132 | btrfs_set_disk_key_offset(&disk_key, offset + size_diff); | |
3133 | btrfs_set_item_key(leaf, &disk_key, slot); | |
3134 | if (slot == 0) | |
3135 | fixup_low_keys(trans, root, path, &disk_key, 1); | |
3136 | } | |
5f39d397 CM |
3137 | |
3138 | item = btrfs_item_nr(leaf, slot); | |
3139 | btrfs_set_item_size(leaf, item, new_size); | |
3140 | btrfs_mark_buffer_dirty(leaf); | |
b18c6685 CM |
3141 | |
3142 | ret = 0; | |
5f39d397 CM |
3143 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
3144 | btrfs_print_leaf(root, leaf); | |
b18c6685 | 3145 | BUG(); |
5f39d397 | 3146 | } |
b18c6685 CM |
3147 | return ret; |
3148 | } | |
3149 | ||
d352ac68 CM |
3150 | /* |
3151 | * make the item pointed to by the path bigger, data_size is the new size. | |
3152 | */ | |
5f39d397 CM |
3153 | int btrfs_extend_item(struct btrfs_trans_handle *trans, |
3154 | struct btrfs_root *root, struct btrfs_path *path, | |
3155 | u32 data_size) | |
6567e837 CM |
3156 | { |
3157 | int ret = 0; | |
3158 | int slot; | |
3159 | int slot_orig; | |
5f39d397 CM |
3160 | struct extent_buffer *leaf; |
3161 | struct btrfs_item *item; | |
6567e837 CM |
3162 | u32 nritems; |
3163 | unsigned int data_end; | |
3164 | unsigned int old_data; | |
3165 | unsigned int old_size; | |
3166 | int i; | |
3167 | ||
3168 | slot_orig = path->slots[0]; | |
5f39d397 | 3169 | leaf = path->nodes[0]; |
6567e837 | 3170 | |
5f39d397 | 3171 | nritems = btrfs_header_nritems(leaf); |
6567e837 CM |
3172 | data_end = leaf_data_end(root, leaf); |
3173 | ||
5f39d397 CM |
3174 | if (btrfs_leaf_free_space(root, leaf) < data_size) { |
3175 | btrfs_print_leaf(root, leaf); | |
6567e837 | 3176 | BUG(); |
5f39d397 | 3177 | } |
6567e837 | 3178 | slot = path->slots[0]; |
5f39d397 | 3179 | old_data = btrfs_item_end_nr(leaf, slot); |
6567e837 CM |
3180 | |
3181 | BUG_ON(slot < 0); | |
3326d1b0 CM |
3182 | if (slot >= nritems) { |
3183 | btrfs_print_leaf(root, leaf); | |
d397712b CM |
3184 | printk(KERN_CRIT "slot %d too large, nritems %d\n", |
3185 | slot, nritems); | |
3326d1b0 CM |
3186 | BUG_ON(1); |
3187 | } | |
6567e837 CM |
3188 | |
3189 | /* | |
3190 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
3191 | */ | |
3192 | /* first correct the data pointers */ | |
3193 | for (i = slot; i < nritems; i++) { | |
5f39d397 CM |
3194 | u32 ioff; |
3195 | item = btrfs_item_nr(leaf, i); | |
db94535d CM |
3196 | |
3197 | if (!leaf->map_token) { | |
3198 | map_extent_buffer(leaf, (unsigned long)item, | |
3199 | sizeof(struct btrfs_item), | |
3200 | &leaf->map_token, &leaf->kaddr, | |
3201 | &leaf->map_start, &leaf->map_len, | |
3202 | KM_USER1); | |
3203 | } | |
5f39d397 CM |
3204 | ioff = btrfs_item_offset(leaf, item); |
3205 | btrfs_set_item_offset(leaf, item, ioff - data_size); | |
6567e837 | 3206 | } |
5f39d397 | 3207 | |
db94535d CM |
3208 | if (leaf->map_token) { |
3209 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
3210 | leaf->map_token = NULL; | |
3211 | } | |
3212 | ||
6567e837 | 3213 | /* shift the data */ |
5f39d397 | 3214 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
6567e837 CM |
3215 | data_end - data_size, btrfs_leaf_data(leaf) + |
3216 | data_end, old_data - data_end); | |
5f39d397 | 3217 | |
6567e837 | 3218 | data_end = old_data; |
5f39d397 CM |
3219 | old_size = btrfs_item_size_nr(leaf, slot); |
3220 | item = btrfs_item_nr(leaf, slot); | |
3221 | btrfs_set_item_size(leaf, item, old_size + data_size); | |
3222 | btrfs_mark_buffer_dirty(leaf); | |
6567e837 CM |
3223 | |
3224 | ret = 0; | |
5f39d397 CM |
3225 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
3226 | btrfs_print_leaf(root, leaf); | |
6567e837 | 3227 | BUG(); |
5f39d397 | 3228 | } |
6567e837 CM |
3229 | return ret; |
3230 | } | |
3231 | ||
f3465ca4 JB |
3232 | /* |
3233 | * Given a key and some data, insert items into the tree. | |
3234 | * This does all the path init required, making room in the tree if needed. | |
3235 | * Returns the number of keys that were inserted. | |
3236 | */ | |
3237 | int btrfs_insert_some_items(struct btrfs_trans_handle *trans, | |
3238 | struct btrfs_root *root, | |
3239 | struct btrfs_path *path, | |
3240 | struct btrfs_key *cpu_key, u32 *data_size, | |
3241 | int nr) | |
3242 | { | |
3243 | struct extent_buffer *leaf; | |
3244 | struct btrfs_item *item; | |
3245 | int ret = 0; | |
3246 | int slot; | |
f3465ca4 JB |
3247 | int i; |
3248 | u32 nritems; | |
3249 | u32 total_data = 0; | |
3250 | u32 total_size = 0; | |
3251 | unsigned int data_end; | |
3252 | struct btrfs_disk_key disk_key; | |
3253 | struct btrfs_key found_key; | |
3254 | ||
87b29b20 YZ |
3255 | for (i = 0; i < nr; i++) { |
3256 | if (total_size + data_size[i] + sizeof(struct btrfs_item) > | |
3257 | BTRFS_LEAF_DATA_SIZE(root)) { | |
3258 | break; | |
3259 | nr = i; | |
3260 | } | |
f3465ca4 | 3261 | total_data += data_size[i]; |
87b29b20 YZ |
3262 | total_size += data_size[i] + sizeof(struct btrfs_item); |
3263 | } | |
3264 | BUG_ON(nr == 0); | |
f3465ca4 | 3265 | |
f3465ca4 JB |
3266 | ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1); |
3267 | if (ret == 0) | |
3268 | return -EEXIST; | |
3269 | if (ret < 0) | |
3270 | goto out; | |
3271 | ||
f3465ca4 JB |
3272 | leaf = path->nodes[0]; |
3273 | ||
3274 | nritems = btrfs_header_nritems(leaf); | |
3275 | data_end = leaf_data_end(root, leaf); | |
3276 | ||
3277 | if (btrfs_leaf_free_space(root, leaf) < total_size) { | |
3278 | for (i = nr; i >= 0; i--) { | |
3279 | total_data -= data_size[i]; | |
3280 | total_size -= data_size[i] + sizeof(struct btrfs_item); | |
3281 | if (total_size < btrfs_leaf_free_space(root, leaf)) | |
3282 | break; | |
3283 | } | |
3284 | nr = i; | |
3285 | } | |
3286 | ||
3287 | slot = path->slots[0]; | |
3288 | BUG_ON(slot < 0); | |
3289 | ||
3290 | if (slot != nritems) { | |
3291 | unsigned int old_data = btrfs_item_end_nr(leaf, slot); | |
3292 | ||
3293 | item = btrfs_item_nr(leaf, slot); | |
3294 | btrfs_item_key_to_cpu(leaf, &found_key, slot); | |
3295 | ||
3296 | /* figure out how many keys we can insert in here */ | |
3297 | total_data = data_size[0]; | |
3298 | for (i = 1; i < nr; i++) { | |
3299 | if (comp_cpu_keys(&found_key, cpu_key + i) <= 0) | |
3300 | break; | |
3301 | total_data += data_size[i]; | |
3302 | } | |
3303 | nr = i; | |
3304 | ||
3305 | if (old_data < data_end) { | |
3306 | btrfs_print_leaf(root, leaf); | |
d397712b | 3307 | printk(KERN_CRIT "slot %d old_data %d data_end %d\n", |
f3465ca4 JB |
3308 | slot, old_data, data_end); |
3309 | BUG_ON(1); | |
3310 | } | |
3311 | /* | |
3312 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
3313 | */ | |
3314 | /* first correct the data pointers */ | |
3315 | WARN_ON(leaf->map_token); | |
3316 | for (i = slot; i < nritems; i++) { | |
3317 | u32 ioff; | |
3318 | ||
3319 | item = btrfs_item_nr(leaf, i); | |
3320 | if (!leaf->map_token) { | |
3321 | map_extent_buffer(leaf, (unsigned long)item, | |
3322 | sizeof(struct btrfs_item), | |
3323 | &leaf->map_token, &leaf->kaddr, | |
3324 | &leaf->map_start, &leaf->map_len, | |
3325 | KM_USER1); | |
3326 | } | |
3327 | ||
3328 | ioff = btrfs_item_offset(leaf, item); | |
3329 | btrfs_set_item_offset(leaf, item, ioff - total_data); | |
3330 | } | |
3331 | if (leaf->map_token) { | |
3332 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
3333 | leaf->map_token = NULL; | |
3334 | } | |
3335 | ||
3336 | /* shift the items */ | |
3337 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr), | |
3338 | btrfs_item_nr_offset(slot), | |
3339 | (nritems - slot) * sizeof(struct btrfs_item)); | |
3340 | ||
3341 | /* shift the data */ | |
3342 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
3343 | data_end - total_data, btrfs_leaf_data(leaf) + | |
3344 | data_end, old_data - data_end); | |
3345 | data_end = old_data; | |
3346 | } else { | |
3347 | /* | |
3348 | * this sucks but it has to be done, if we are inserting at | |
3349 | * the end of the leaf only insert 1 of the items, since we | |
3350 | * have no way of knowing whats on the next leaf and we'd have | |
3351 | * to drop our current locks to figure it out | |
3352 | */ | |
3353 | nr = 1; | |
3354 | } | |
3355 | ||
3356 | /* setup the item for the new data */ | |
3357 | for (i = 0; i < nr; i++) { | |
3358 | btrfs_cpu_key_to_disk(&disk_key, cpu_key + i); | |
3359 | btrfs_set_item_key(leaf, &disk_key, slot + i); | |
3360 | item = btrfs_item_nr(leaf, slot + i); | |
3361 | btrfs_set_item_offset(leaf, item, data_end - data_size[i]); | |
3362 | data_end -= data_size[i]; | |
3363 | btrfs_set_item_size(leaf, item, data_size[i]); | |
3364 | } | |
3365 | btrfs_set_header_nritems(leaf, nritems + nr); | |
3366 | btrfs_mark_buffer_dirty(leaf); | |
3367 | ||
3368 | ret = 0; | |
3369 | if (slot == 0) { | |
3370 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); | |
3371 | ret = fixup_low_keys(trans, root, path, &disk_key, 1); | |
3372 | } | |
3373 | ||
3374 | if (btrfs_leaf_free_space(root, leaf) < 0) { | |
3375 | btrfs_print_leaf(root, leaf); | |
3376 | BUG(); | |
3377 | } | |
3378 | out: | |
3379 | if (!ret) | |
3380 | ret = nr; | |
3381 | return ret; | |
3382 | } | |
3383 | ||
74123bd7 | 3384 | /* |
d352ac68 | 3385 | * Given a key and some data, insert items into the tree. |
74123bd7 CM |
3386 | * This does all the path init required, making room in the tree if needed. |
3387 | */ | |
9c58309d | 3388 | int btrfs_insert_empty_items(struct btrfs_trans_handle *trans, |
5f39d397 CM |
3389 | struct btrfs_root *root, |
3390 | struct btrfs_path *path, | |
9c58309d CM |
3391 | struct btrfs_key *cpu_key, u32 *data_size, |
3392 | int nr) | |
be0e5c09 | 3393 | { |
5f39d397 CM |
3394 | struct extent_buffer *leaf; |
3395 | struct btrfs_item *item; | |
aa5d6bed | 3396 | int ret = 0; |
be0e5c09 | 3397 | int slot; |
eb60ceac | 3398 | int slot_orig; |
9c58309d | 3399 | int i; |
7518a238 | 3400 | u32 nritems; |
9c58309d CM |
3401 | u32 total_size = 0; |
3402 | u32 total_data = 0; | |
be0e5c09 | 3403 | unsigned int data_end; |
e2fa7227 CM |
3404 | struct btrfs_disk_key disk_key; |
3405 | ||
d397712b | 3406 | for (i = 0; i < nr; i++) |
9c58309d | 3407 | total_data += data_size[i]; |
be0e5c09 | 3408 | |
7b128766 | 3409 | total_size = total_data + (nr * sizeof(struct btrfs_item)); |
9c58309d | 3410 | ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1); |
0f9dd46c | 3411 | if (ret == 0) |
f0930a37 | 3412 | return -EEXIST; |
ed2ff2cb CM |
3413 | if (ret < 0) |
3414 | goto out; | |
be0e5c09 | 3415 | |
62e2749e | 3416 | slot_orig = path->slots[0]; |
5f39d397 | 3417 | leaf = path->nodes[0]; |
74123bd7 | 3418 | |
5f39d397 | 3419 | nritems = btrfs_header_nritems(leaf); |
123abc88 | 3420 | data_end = leaf_data_end(root, leaf); |
eb60ceac | 3421 | |
f25956cc | 3422 | if (btrfs_leaf_free_space(root, leaf) < total_size) { |
3326d1b0 | 3423 | btrfs_print_leaf(root, leaf); |
d397712b | 3424 | printk(KERN_CRIT "not enough freespace need %u have %d\n", |
9c58309d | 3425 | total_size, btrfs_leaf_free_space(root, leaf)); |
be0e5c09 | 3426 | BUG(); |
d4dbff95 | 3427 | } |
5f39d397 | 3428 | |
62e2749e | 3429 | slot = path->slots[0]; |
eb60ceac | 3430 | BUG_ON(slot < 0); |
5f39d397 | 3431 | |
be0e5c09 | 3432 | if (slot != nritems) { |
5f39d397 | 3433 | unsigned int old_data = btrfs_item_end_nr(leaf, slot); |
be0e5c09 | 3434 | |
5f39d397 CM |
3435 | if (old_data < data_end) { |
3436 | btrfs_print_leaf(root, leaf); | |
d397712b | 3437 | printk(KERN_CRIT "slot %d old_data %d data_end %d\n", |
5f39d397 CM |
3438 | slot, old_data, data_end); |
3439 | BUG_ON(1); | |
3440 | } | |
be0e5c09 CM |
3441 | /* |
3442 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
3443 | */ | |
3444 | /* first correct the data pointers */ | |
db94535d | 3445 | WARN_ON(leaf->map_token); |
0783fcfc | 3446 | for (i = slot; i < nritems; i++) { |
5f39d397 | 3447 | u32 ioff; |
db94535d | 3448 | |
5f39d397 | 3449 | item = btrfs_item_nr(leaf, i); |
db94535d CM |
3450 | if (!leaf->map_token) { |
3451 | map_extent_buffer(leaf, (unsigned long)item, | |
3452 | sizeof(struct btrfs_item), | |
3453 | &leaf->map_token, &leaf->kaddr, | |
3454 | &leaf->map_start, &leaf->map_len, | |
3455 | KM_USER1); | |
3456 | } | |
3457 | ||
5f39d397 | 3458 | ioff = btrfs_item_offset(leaf, item); |
9c58309d | 3459 | btrfs_set_item_offset(leaf, item, ioff - total_data); |
0783fcfc | 3460 | } |
db94535d CM |
3461 | if (leaf->map_token) { |
3462 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
3463 | leaf->map_token = NULL; | |
3464 | } | |
be0e5c09 CM |
3465 | |
3466 | /* shift the items */ | |
9c58309d | 3467 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr), |
5f39d397 | 3468 | btrfs_item_nr_offset(slot), |
d6025579 | 3469 | (nritems - slot) * sizeof(struct btrfs_item)); |
be0e5c09 CM |
3470 | |
3471 | /* shift the data */ | |
5f39d397 | 3472 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
9c58309d | 3473 | data_end - total_data, btrfs_leaf_data(leaf) + |
d6025579 | 3474 | data_end, old_data - data_end); |
be0e5c09 CM |
3475 | data_end = old_data; |
3476 | } | |
5f39d397 | 3477 | |
62e2749e | 3478 | /* setup the item for the new data */ |
9c58309d CM |
3479 | for (i = 0; i < nr; i++) { |
3480 | btrfs_cpu_key_to_disk(&disk_key, cpu_key + i); | |
3481 | btrfs_set_item_key(leaf, &disk_key, slot + i); | |
3482 | item = btrfs_item_nr(leaf, slot + i); | |
3483 | btrfs_set_item_offset(leaf, item, data_end - data_size[i]); | |
3484 | data_end -= data_size[i]; | |
3485 | btrfs_set_item_size(leaf, item, data_size[i]); | |
3486 | } | |
3487 | btrfs_set_header_nritems(leaf, nritems + nr); | |
5f39d397 | 3488 | btrfs_mark_buffer_dirty(leaf); |
aa5d6bed CM |
3489 | |
3490 | ret = 0; | |
5a01a2e3 CM |
3491 | if (slot == 0) { |
3492 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); | |
e089f05c | 3493 | ret = fixup_low_keys(trans, root, path, &disk_key, 1); |
5a01a2e3 | 3494 | } |
aa5d6bed | 3495 | |
5f39d397 CM |
3496 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
3497 | btrfs_print_leaf(root, leaf); | |
be0e5c09 | 3498 | BUG(); |
5f39d397 | 3499 | } |
ed2ff2cb | 3500 | out: |
b4ce94de | 3501 | btrfs_unlock_up_safe(path, 1); |
62e2749e CM |
3502 | return ret; |
3503 | } | |
3504 | ||
3505 | /* | |
3506 | * Given a key and some data, insert an item into the tree. | |
3507 | * This does all the path init required, making room in the tree if needed. | |
3508 | */ | |
e089f05c CM |
3509 | int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root |
3510 | *root, struct btrfs_key *cpu_key, void *data, u32 | |
3511 | data_size) | |
62e2749e CM |
3512 | { |
3513 | int ret = 0; | |
2c90e5d6 | 3514 | struct btrfs_path *path; |
5f39d397 CM |
3515 | struct extent_buffer *leaf; |
3516 | unsigned long ptr; | |
62e2749e | 3517 | |
2c90e5d6 CM |
3518 | path = btrfs_alloc_path(); |
3519 | BUG_ON(!path); | |
2c90e5d6 | 3520 | ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size); |
62e2749e | 3521 | if (!ret) { |
5f39d397 CM |
3522 | leaf = path->nodes[0]; |
3523 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
3524 | write_extent_buffer(leaf, data, ptr, data_size); | |
3525 | btrfs_mark_buffer_dirty(leaf); | |
62e2749e | 3526 | } |
2c90e5d6 | 3527 | btrfs_free_path(path); |
aa5d6bed | 3528 | return ret; |
be0e5c09 CM |
3529 | } |
3530 | ||
74123bd7 | 3531 | /* |
5de08d7d | 3532 | * delete the pointer from a given node. |
74123bd7 | 3533 | * |
d352ac68 CM |
3534 | * the tree should have been previously balanced so the deletion does not |
3535 | * empty a node. | |
74123bd7 | 3536 | */ |
e089f05c CM |
3537 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
3538 | struct btrfs_path *path, int level, int slot) | |
be0e5c09 | 3539 | { |
5f39d397 | 3540 | struct extent_buffer *parent = path->nodes[level]; |
7518a238 | 3541 | u32 nritems; |
aa5d6bed | 3542 | int ret = 0; |
bb803951 | 3543 | int wret; |
be0e5c09 | 3544 | |
5f39d397 | 3545 | nritems = btrfs_header_nritems(parent); |
d397712b | 3546 | if (slot != nritems - 1) { |
5f39d397 CM |
3547 | memmove_extent_buffer(parent, |
3548 | btrfs_node_key_ptr_offset(slot), | |
3549 | btrfs_node_key_ptr_offset(slot + 1), | |
d6025579 CM |
3550 | sizeof(struct btrfs_key_ptr) * |
3551 | (nritems - slot - 1)); | |
bb803951 | 3552 | } |
7518a238 | 3553 | nritems--; |
5f39d397 | 3554 | btrfs_set_header_nritems(parent, nritems); |
7518a238 | 3555 | if (nritems == 0 && parent == root->node) { |
5f39d397 | 3556 | BUG_ON(btrfs_header_level(root->node) != 1); |
bb803951 | 3557 | /* just turn the root into a leaf and break */ |
5f39d397 | 3558 | btrfs_set_header_level(root->node, 0); |
bb803951 | 3559 | } else if (slot == 0) { |
5f39d397 CM |
3560 | struct btrfs_disk_key disk_key; |
3561 | ||
3562 | btrfs_node_key(parent, &disk_key, 0); | |
3563 | wret = fixup_low_keys(trans, root, path, &disk_key, level + 1); | |
0f70abe2 CM |
3564 | if (wret) |
3565 | ret = wret; | |
be0e5c09 | 3566 | } |
d6025579 | 3567 | btrfs_mark_buffer_dirty(parent); |
aa5d6bed | 3568 | return ret; |
be0e5c09 CM |
3569 | } |
3570 | ||
323ac95b CM |
3571 | /* |
3572 | * a helper function to delete the leaf pointed to by path->slots[1] and | |
3573 | * path->nodes[1]. bytenr is the node block pointer, but since the callers | |
3574 | * already know it, it is faster to have them pass it down than to | |
3575 | * read it out of the node again. | |
3576 | * | |
3577 | * This deletes the pointer in path->nodes[1] and frees the leaf | |
3578 | * block extent. zero is returned if it all worked out, < 0 otherwise. | |
3579 | * | |
3580 | * The path must have already been setup for deleting the leaf, including | |
3581 | * all the proper balancing. path->nodes[1] must be locked. | |
3582 | */ | |
3583 | noinline int btrfs_del_leaf(struct btrfs_trans_handle *trans, | |
3584 | struct btrfs_root *root, | |
3585 | struct btrfs_path *path, u64 bytenr) | |
3586 | { | |
3587 | int ret; | |
3588 | u64 root_gen = btrfs_header_generation(path->nodes[1]); | |
4d081c41 CM |
3589 | u64 parent_start = path->nodes[1]->start; |
3590 | u64 parent_owner = btrfs_header_owner(path->nodes[1]); | |
323ac95b CM |
3591 | |
3592 | ret = del_ptr(trans, root, path, 1, path->slots[1]); | |
3593 | if (ret) | |
3594 | return ret; | |
3595 | ||
4d081c41 CM |
3596 | /* |
3597 | * btrfs_free_extent is expensive, we want to make sure we | |
3598 | * aren't holding any locks when we call it | |
3599 | */ | |
3600 | btrfs_unlock_up_safe(path, 0); | |
3601 | ||
323ac95b CM |
3602 | ret = btrfs_free_extent(trans, root, bytenr, |
3603 | btrfs_level_size(root, 0), | |
4d081c41 | 3604 | parent_start, parent_owner, |
3bb1a1bc | 3605 | root_gen, 0, 1); |
323ac95b CM |
3606 | return ret; |
3607 | } | |
74123bd7 CM |
3608 | /* |
3609 | * delete the item at the leaf level in path. If that empties | |
3610 | * the leaf, remove it from the tree | |
3611 | */ | |
85e21bac CM |
3612 | int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
3613 | struct btrfs_path *path, int slot, int nr) | |
be0e5c09 | 3614 | { |
5f39d397 CM |
3615 | struct extent_buffer *leaf; |
3616 | struct btrfs_item *item; | |
85e21bac CM |
3617 | int last_off; |
3618 | int dsize = 0; | |
aa5d6bed CM |
3619 | int ret = 0; |
3620 | int wret; | |
85e21bac | 3621 | int i; |
7518a238 | 3622 | u32 nritems; |
be0e5c09 | 3623 | |
5f39d397 | 3624 | leaf = path->nodes[0]; |
85e21bac CM |
3625 | last_off = btrfs_item_offset_nr(leaf, slot + nr - 1); |
3626 | ||
3627 | for (i = 0; i < nr; i++) | |
3628 | dsize += btrfs_item_size_nr(leaf, slot + i); | |
3629 | ||
5f39d397 | 3630 | nritems = btrfs_header_nritems(leaf); |
be0e5c09 | 3631 | |
85e21bac | 3632 | if (slot + nr != nritems) { |
123abc88 | 3633 | int data_end = leaf_data_end(root, leaf); |
5f39d397 CM |
3634 | |
3635 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
d6025579 CM |
3636 | data_end + dsize, |
3637 | btrfs_leaf_data(leaf) + data_end, | |
85e21bac | 3638 | last_off - data_end); |
5f39d397 | 3639 | |
85e21bac | 3640 | for (i = slot + nr; i < nritems; i++) { |
5f39d397 | 3641 | u32 ioff; |
db94535d | 3642 | |
5f39d397 | 3643 | item = btrfs_item_nr(leaf, i); |
db94535d CM |
3644 | if (!leaf->map_token) { |
3645 | map_extent_buffer(leaf, (unsigned long)item, | |
3646 | sizeof(struct btrfs_item), | |
3647 | &leaf->map_token, &leaf->kaddr, | |
3648 | &leaf->map_start, &leaf->map_len, | |
3649 | KM_USER1); | |
3650 | } | |
5f39d397 CM |
3651 | ioff = btrfs_item_offset(leaf, item); |
3652 | btrfs_set_item_offset(leaf, item, ioff + dsize); | |
0783fcfc | 3653 | } |
db94535d CM |
3654 | |
3655 | if (leaf->map_token) { | |
3656 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
3657 | leaf->map_token = NULL; | |
3658 | } | |
3659 | ||
5f39d397 | 3660 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot), |
85e21bac | 3661 | btrfs_item_nr_offset(slot + nr), |
d6025579 | 3662 | sizeof(struct btrfs_item) * |
85e21bac | 3663 | (nritems - slot - nr)); |
be0e5c09 | 3664 | } |
85e21bac CM |
3665 | btrfs_set_header_nritems(leaf, nritems - nr); |
3666 | nritems -= nr; | |
5f39d397 | 3667 | |
74123bd7 | 3668 | /* delete the leaf if we've emptied it */ |
7518a238 | 3669 | if (nritems == 0) { |
5f39d397 CM |
3670 | if (leaf == root->node) { |
3671 | btrfs_set_header_level(leaf, 0); | |
9a8dd150 | 3672 | } else { |
323ac95b CM |
3673 | ret = btrfs_del_leaf(trans, root, path, leaf->start); |
3674 | BUG_ON(ret); | |
9a8dd150 | 3675 | } |
be0e5c09 | 3676 | } else { |
7518a238 | 3677 | int used = leaf_space_used(leaf, 0, nritems); |
aa5d6bed | 3678 | if (slot == 0) { |
5f39d397 CM |
3679 | struct btrfs_disk_key disk_key; |
3680 | ||
3681 | btrfs_item_key(leaf, &disk_key, 0); | |
e089f05c | 3682 | wret = fixup_low_keys(trans, root, path, |
5f39d397 | 3683 | &disk_key, 1); |
aa5d6bed CM |
3684 | if (wret) |
3685 | ret = wret; | |
3686 | } | |
aa5d6bed | 3687 | |
74123bd7 | 3688 | /* delete the leaf if it is mostly empty */ |
85e21bac | 3689 | if (used < BTRFS_LEAF_DATA_SIZE(root) / 4) { |
be0e5c09 CM |
3690 | /* push_leaf_left fixes the path. |
3691 | * make sure the path still points to our leaf | |
3692 | * for possible call to del_ptr below | |
3693 | */ | |
4920c9ac | 3694 | slot = path->slots[1]; |
5f39d397 CM |
3695 | extent_buffer_get(leaf); |
3696 | ||
85e21bac | 3697 | wret = push_leaf_left(trans, root, path, 1, 1); |
54aa1f4d | 3698 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed | 3699 | ret = wret; |
5f39d397 CM |
3700 | |
3701 | if (path->nodes[0] == leaf && | |
3702 | btrfs_header_nritems(leaf)) { | |
85e21bac | 3703 | wret = push_leaf_right(trans, root, path, 1, 1); |
54aa1f4d | 3704 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed CM |
3705 | ret = wret; |
3706 | } | |
5f39d397 CM |
3707 | |
3708 | if (btrfs_header_nritems(leaf) == 0) { | |
323ac95b | 3709 | path->slots[1] = slot; |
d397712b CM |
3710 | ret = btrfs_del_leaf(trans, root, path, |
3711 | leaf->start); | |
323ac95b | 3712 | BUG_ON(ret); |
5f39d397 | 3713 | free_extent_buffer(leaf); |
5de08d7d | 3714 | } else { |
925baedd CM |
3715 | /* if we're still in the path, make sure |
3716 | * we're dirty. Otherwise, one of the | |
3717 | * push_leaf functions must have already | |
3718 | * dirtied this buffer | |
3719 | */ | |
3720 | if (path->nodes[0] == leaf) | |
3721 | btrfs_mark_buffer_dirty(leaf); | |
5f39d397 | 3722 | free_extent_buffer(leaf); |
be0e5c09 | 3723 | } |
d5719762 | 3724 | } else { |
5f39d397 | 3725 | btrfs_mark_buffer_dirty(leaf); |
be0e5c09 CM |
3726 | } |
3727 | } | |
aa5d6bed | 3728 | return ret; |
be0e5c09 CM |
3729 | } |
3730 | ||
7bb86316 | 3731 | /* |
925baedd | 3732 | * search the tree again to find a leaf with lesser keys |
7bb86316 CM |
3733 | * returns 0 if it found something or 1 if there are no lesser leaves. |
3734 | * returns < 0 on io errors. | |
d352ac68 CM |
3735 | * |
3736 | * This may release the path, and so you may lose any locks held at the | |
3737 | * time you call it. | |
7bb86316 CM |
3738 | */ |
3739 | int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path) | |
3740 | { | |
925baedd CM |
3741 | struct btrfs_key key; |
3742 | struct btrfs_disk_key found_key; | |
3743 | int ret; | |
7bb86316 | 3744 | |
925baedd | 3745 | btrfs_item_key_to_cpu(path->nodes[0], &key, 0); |
7bb86316 | 3746 | |
925baedd CM |
3747 | if (key.offset > 0) |
3748 | key.offset--; | |
3749 | else if (key.type > 0) | |
3750 | key.type--; | |
3751 | else if (key.objectid > 0) | |
3752 | key.objectid--; | |
3753 | else | |
3754 | return 1; | |
7bb86316 | 3755 | |
925baedd CM |
3756 | btrfs_release_path(root, path); |
3757 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
3758 | if (ret < 0) | |
3759 | return ret; | |
3760 | btrfs_item_key(path->nodes[0], &found_key, 0); | |
3761 | ret = comp_keys(&found_key, &key); | |
3762 | if (ret < 0) | |
3763 | return 0; | |
3764 | return 1; | |
7bb86316 CM |
3765 | } |
3766 | ||
3f157a2f CM |
3767 | /* |
3768 | * A helper function to walk down the tree starting at min_key, and looking | |
3769 | * for nodes or leaves that are either in cache or have a minimum | |
d352ac68 | 3770 | * transaction id. This is used by the btree defrag code, and tree logging |
3f157a2f CM |
3771 | * |
3772 | * This does not cow, but it does stuff the starting key it finds back | |
3773 | * into min_key, so you can call btrfs_search_slot with cow=1 on the | |
3774 | * key and get a writable path. | |
3775 | * | |
3776 | * This does lock as it descends, and path->keep_locks should be set | |
3777 | * to 1 by the caller. | |
3778 | * | |
3779 | * This honors path->lowest_level to prevent descent past a given level | |
3780 | * of the tree. | |
3781 | * | |
d352ac68 CM |
3782 | * min_trans indicates the oldest transaction that you are interested |
3783 | * in walking through. Any nodes or leaves older than min_trans are | |
3784 | * skipped over (without reading them). | |
3785 | * | |
3f157a2f CM |
3786 | * returns zero if something useful was found, < 0 on error and 1 if there |
3787 | * was nothing in the tree that matched the search criteria. | |
3788 | */ | |
3789 | int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key, | |
e02119d5 | 3790 | struct btrfs_key *max_key, |
3f157a2f CM |
3791 | struct btrfs_path *path, int cache_only, |
3792 | u64 min_trans) | |
3793 | { | |
3794 | struct extent_buffer *cur; | |
3795 | struct btrfs_key found_key; | |
3796 | int slot; | |
9652480b | 3797 | int sret; |
3f157a2f CM |
3798 | u32 nritems; |
3799 | int level; | |
3800 | int ret = 1; | |
3801 | ||
934d375b | 3802 | WARN_ON(!path->keep_locks); |
3f157a2f CM |
3803 | again: |
3804 | cur = btrfs_lock_root_node(root); | |
3805 | level = btrfs_header_level(cur); | |
e02119d5 | 3806 | WARN_ON(path->nodes[level]); |
3f157a2f CM |
3807 | path->nodes[level] = cur; |
3808 | path->locks[level] = 1; | |
3809 | ||
3810 | if (btrfs_header_generation(cur) < min_trans) { | |
3811 | ret = 1; | |
3812 | goto out; | |
3813 | } | |
d397712b | 3814 | while (1) { |
3f157a2f CM |
3815 | nritems = btrfs_header_nritems(cur); |
3816 | level = btrfs_header_level(cur); | |
9652480b | 3817 | sret = bin_search(cur, min_key, level, &slot); |
3f157a2f | 3818 | |
323ac95b CM |
3819 | /* at the lowest level, we're done, setup the path and exit */ |
3820 | if (level == path->lowest_level) { | |
e02119d5 CM |
3821 | if (slot >= nritems) |
3822 | goto find_next_key; | |
3f157a2f CM |
3823 | ret = 0; |
3824 | path->slots[level] = slot; | |
3825 | btrfs_item_key_to_cpu(cur, &found_key, slot); | |
3826 | goto out; | |
3827 | } | |
9652480b Y |
3828 | if (sret && slot > 0) |
3829 | slot--; | |
3f157a2f CM |
3830 | /* |
3831 | * check this node pointer against the cache_only and | |
3832 | * min_trans parameters. If it isn't in cache or is too | |
3833 | * old, skip to the next one. | |
3834 | */ | |
d397712b | 3835 | while (slot < nritems) { |
3f157a2f CM |
3836 | u64 blockptr; |
3837 | u64 gen; | |
3838 | struct extent_buffer *tmp; | |
e02119d5 CM |
3839 | struct btrfs_disk_key disk_key; |
3840 | ||
3f157a2f CM |
3841 | blockptr = btrfs_node_blockptr(cur, slot); |
3842 | gen = btrfs_node_ptr_generation(cur, slot); | |
3843 | if (gen < min_trans) { | |
3844 | slot++; | |
3845 | continue; | |
3846 | } | |
3847 | if (!cache_only) | |
3848 | break; | |
3849 | ||
e02119d5 CM |
3850 | if (max_key) { |
3851 | btrfs_node_key(cur, &disk_key, slot); | |
3852 | if (comp_keys(&disk_key, max_key) >= 0) { | |
3853 | ret = 1; | |
3854 | goto out; | |
3855 | } | |
3856 | } | |
3857 | ||
3f157a2f CM |
3858 | tmp = btrfs_find_tree_block(root, blockptr, |
3859 | btrfs_level_size(root, level - 1)); | |
3860 | ||
3861 | if (tmp && btrfs_buffer_uptodate(tmp, gen)) { | |
3862 | free_extent_buffer(tmp); | |
3863 | break; | |
3864 | } | |
3865 | if (tmp) | |
3866 | free_extent_buffer(tmp); | |
3867 | slot++; | |
3868 | } | |
e02119d5 | 3869 | find_next_key: |
3f157a2f CM |
3870 | /* |
3871 | * we didn't find a candidate key in this node, walk forward | |
3872 | * and find another one | |
3873 | */ | |
3874 | if (slot >= nritems) { | |
e02119d5 | 3875 | path->slots[level] = slot; |
b4ce94de | 3876 | btrfs_set_path_blocking(path); |
e02119d5 | 3877 | sret = btrfs_find_next_key(root, path, min_key, level, |
3f157a2f | 3878 | cache_only, min_trans); |
e02119d5 | 3879 | if (sret == 0) { |
3f157a2f CM |
3880 | btrfs_release_path(root, path); |
3881 | goto again; | |
3882 | } else { | |
3883 | goto out; | |
3884 | } | |
3885 | } | |
3886 | /* save our key for returning back */ | |
3887 | btrfs_node_key_to_cpu(cur, &found_key, slot); | |
3888 | path->slots[level] = slot; | |
3889 | if (level == path->lowest_level) { | |
3890 | ret = 0; | |
3891 | unlock_up(path, level, 1); | |
3892 | goto out; | |
3893 | } | |
b4ce94de | 3894 | btrfs_set_path_blocking(path); |
3f157a2f CM |
3895 | cur = read_node_slot(root, cur, slot); |
3896 | ||
3897 | btrfs_tree_lock(cur); | |
b4ce94de | 3898 | |
3f157a2f CM |
3899 | path->locks[level - 1] = 1; |
3900 | path->nodes[level - 1] = cur; | |
3901 | unlock_up(path, level, 1); | |
4008c04a | 3902 | btrfs_clear_path_blocking(path, NULL); |
3f157a2f CM |
3903 | } |
3904 | out: | |
3905 | if (ret == 0) | |
3906 | memcpy(min_key, &found_key, sizeof(found_key)); | |
b4ce94de | 3907 | btrfs_set_path_blocking(path); |
3f157a2f CM |
3908 | return ret; |
3909 | } | |
3910 | ||
3911 | /* | |
3912 | * this is similar to btrfs_next_leaf, but does not try to preserve | |
3913 | * and fixup the path. It looks for and returns the next key in the | |
3914 | * tree based on the current path and the cache_only and min_trans | |
3915 | * parameters. | |
3916 | * | |
3917 | * 0 is returned if another key is found, < 0 if there are any errors | |
3918 | * and 1 is returned if there are no higher keys in the tree | |
3919 | * | |
3920 | * path->keep_locks should be set to 1 on the search made before | |
3921 | * calling this function. | |
3922 | */ | |
e7a84565 | 3923 | int btrfs_find_next_key(struct btrfs_root *root, struct btrfs_path *path, |
3f157a2f CM |
3924 | struct btrfs_key *key, int lowest_level, |
3925 | int cache_only, u64 min_trans) | |
e7a84565 CM |
3926 | { |
3927 | int level = lowest_level; | |
3928 | int slot; | |
3929 | struct extent_buffer *c; | |
3930 | ||
934d375b | 3931 | WARN_ON(!path->keep_locks); |
d397712b | 3932 | while (level < BTRFS_MAX_LEVEL) { |
e7a84565 CM |
3933 | if (!path->nodes[level]) |
3934 | return 1; | |
3935 | ||
3936 | slot = path->slots[level] + 1; | |
3937 | c = path->nodes[level]; | |
3f157a2f | 3938 | next: |
e7a84565 CM |
3939 | if (slot >= btrfs_header_nritems(c)) { |
3940 | level++; | |
d397712b | 3941 | if (level == BTRFS_MAX_LEVEL) |
e7a84565 | 3942 | return 1; |
e7a84565 CM |
3943 | continue; |
3944 | } | |
3945 | if (level == 0) | |
3946 | btrfs_item_key_to_cpu(c, key, slot); | |
3f157a2f CM |
3947 | else { |
3948 | u64 blockptr = btrfs_node_blockptr(c, slot); | |
3949 | u64 gen = btrfs_node_ptr_generation(c, slot); | |
3950 | ||
3951 | if (cache_only) { | |
3952 | struct extent_buffer *cur; | |
3953 | cur = btrfs_find_tree_block(root, blockptr, | |
3954 | btrfs_level_size(root, level - 1)); | |
3955 | if (!cur || !btrfs_buffer_uptodate(cur, gen)) { | |
3956 | slot++; | |
3957 | if (cur) | |
3958 | free_extent_buffer(cur); | |
3959 | goto next; | |
3960 | } | |
3961 | free_extent_buffer(cur); | |
3962 | } | |
3963 | if (gen < min_trans) { | |
3964 | slot++; | |
3965 | goto next; | |
3966 | } | |
e7a84565 | 3967 | btrfs_node_key_to_cpu(c, key, slot); |
3f157a2f | 3968 | } |
e7a84565 CM |
3969 | return 0; |
3970 | } | |
3971 | return 1; | |
3972 | } | |
3973 | ||
97571fd0 | 3974 | /* |
925baedd | 3975 | * search the tree again to find a leaf with greater keys |
0f70abe2 CM |
3976 | * returns 0 if it found something or 1 if there are no greater leaves. |
3977 | * returns < 0 on io errors. | |
97571fd0 | 3978 | */ |
234b63a0 | 3979 | int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) |
d97e63b6 CM |
3980 | { |
3981 | int slot; | |
3982 | int level = 1; | |
5f39d397 CM |
3983 | struct extent_buffer *c; |
3984 | struct extent_buffer *next = NULL; | |
925baedd CM |
3985 | struct btrfs_key key; |
3986 | u32 nritems; | |
3987 | int ret; | |
3988 | ||
3989 | nritems = btrfs_header_nritems(path->nodes[0]); | |
d397712b | 3990 | if (nritems == 0) |
925baedd | 3991 | return 1; |
925baedd CM |
3992 | |
3993 | btrfs_item_key_to_cpu(path->nodes[0], &key, nritems - 1); | |
3994 | ||
925baedd | 3995 | btrfs_release_path(root, path); |
a2135011 | 3996 | path->keep_locks = 1; |
925baedd CM |
3997 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
3998 | path->keep_locks = 0; | |
3999 | ||
4000 | if (ret < 0) | |
4001 | return ret; | |
4002 | ||
b4ce94de | 4003 | btrfs_set_path_blocking(path); |
a2135011 | 4004 | nritems = btrfs_header_nritems(path->nodes[0]); |
168fd7d2 CM |
4005 | /* |
4006 | * by releasing the path above we dropped all our locks. A balance | |
4007 | * could have added more items next to the key that used to be | |
4008 | * at the very end of the block. So, check again here and | |
4009 | * advance the path if there are now more items available. | |
4010 | */ | |
a2135011 | 4011 | if (nritems > 0 && path->slots[0] < nritems - 1) { |
168fd7d2 | 4012 | path->slots[0]++; |
925baedd CM |
4013 | goto done; |
4014 | } | |
d97e63b6 | 4015 | |
d397712b | 4016 | while (level < BTRFS_MAX_LEVEL) { |
d97e63b6 | 4017 | if (!path->nodes[level]) |
0f70abe2 | 4018 | return 1; |
5f39d397 | 4019 | |
d97e63b6 CM |
4020 | slot = path->slots[level] + 1; |
4021 | c = path->nodes[level]; | |
5f39d397 | 4022 | if (slot >= btrfs_header_nritems(c)) { |
d97e63b6 | 4023 | level++; |
d397712b | 4024 | if (level == BTRFS_MAX_LEVEL) |
7bb86316 | 4025 | return 1; |
d97e63b6 CM |
4026 | continue; |
4027 | } | |
5f39d397 | 4028 | |
925baedd CM |
4029 | if (next) { |
4030 | btrfs_tree_unlock(next); | |
5f39d397 | 4031 | free_extent_buffer(next); |
925baedd | 4032 | } |
5f39d397 | 4033 | |
b4ce94de | 4034 | /* the path was set to blocking above */ |
0bd40a71 CM |
4035 | if (level == 1 && (path->locks[1] || path->skip_locking) && |
4036 | path->reada) | |
01f46658 | 4037 | reada_for_search(root, path, level, slot, 0); |
5f39d397 | 4038 | |
ca7a79ad | 4039 | next = read_node_slot(root, c, slot); |
5cd57b2c | 4040 | if (!path->skip_locking) { |
b9447ef8 | 4041 | btrfs_assert_tree_locked(c); |
5cd57b2c | 4042 | btrfs_tree_lock(next); |
b4ce94de | 4043 | btrfs_set_lock_blocking(next); |
5cd57b2c | 4044 | } |
d97e63b6 CM |
4045 | break; |
4046 | } | |
4047 | path->slots[level] = slot; | |
d397712b | 4048 | while (1) { |
d97e63b6 CM |
4049 | level--; |
4050 | c = path->nodes[level]; | |
925baedd CM |
4051 | if (path->locks[level]) |
4052 | btrfs_tree_unlock(c); | |
5f39d397 | 4053 | free_extent_buffer(c); |
d97e63b6 CM |
4054 | path->nodes[level] = next; |
4055 | path->slots[level] = 0; | |
a74a4b97 CM |
4056 | if (!path->skip_locking) |
4057 | path->locks[level] = 1; | |
d97e63b6 CM |
4058 | if (!level) |
4059 | break; | |
b4ce94de CM |
4060 | |
4061 | btrfs_set_path_blocking(path); | |
925baedd CM |
4062 | if (level == 1 && path->locks[1] && path->reada) |
4063 | reada_for_search(root, path, level, slot, 0); | |
ca7a79ad | 4064 | next = read_node_slot(root, next, 0); |
5cd57b2c | 4065 | if (!path->skip_locking) { |
b9447ef8 | 4066 | btrfs_assert_tree_locked(path->nodes[level]); |
5cd57b2c | 4067 | btrfs_tree_lock(next); |
b4ce94de | 4068 | btrfs_set_lock_blocking(next); |
5cd57b2c | 4069 | } |
d97e63b6 | 4070 | } |
925baedd CM |
4071 | done: |
4072 | unlock_up(path, 0, 1); | |
d97e63b6 CM |
4073 | return 0; |
4074 | } | |
0b86a832 | 4075 | |
3f157a2f CM |
4076 | /* |
4077 | * this uses btrfs_prev_leaf to walk backwards in the tree, and keeps | |
4078 | * searching until it gets past min_objectid or finds an item of 'type' | |
4079 | * | |
4080 | * returns 0 if something is found, 1 if nothing was found and < 0 on error | |
4081 | */ | |
0b86a832 CM |
4082 | int btrfs_previous_item(struct btrfs_root *root, |
4083 | struct btrfs_path *path, u64 min_objectid, | |
4084 | int type) | |
4085 | { | |
4086 | struct btrfs_key found_key; | |
4087 | struct extent_buffer *leaf; | |
e02119d5 | 4088 | u32 nritems; |
0b86a832 CM |
4089 | int ret; |
4090 | ||
d397712b | 4091 | while (1) { |
0b86a832 | 4092 | if (path->slots[0] == 0) { |
b4ce94de | 4093 | btrfs_set_path_blocking(path); |
0b86a832 CM |
4094 | ret = btrfs_prev_leaf(root, path); |
4095 | if (ret != 0) | |
4096 | return ret; | |
4097 | } else { | |
4098 | path->slots[0]--; | |
4099 | } | |
4100 | leaf = path->nodes[0]; | |
e02119d5 CM |
4101 | nritems = btrfs_header_nritems(leaf); |
4102 | if (nritems == 0) | |
4103 | return 1; | |
4104 | if (path->slots[0] == nritems) | |
4105 | path->slots[0]--; | |
4106 | ||
0b86a832 CM |
4107 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
4108 | if (found_key.type == type) | |
4109 | return 0; | |
e02119d5 CM |
4110 | if (found_key.objectid < min_objectid) |
4111 | break; | |
4112 | if (found_key.objectid == min_objectid && | |
4113 | found_key.type < type) | |
4114 | break; | |
0b86a832 CM |
4115 | } |
4116 | return 1; | |
4117 | } |