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6cbd5570 CM |
1 | /* |
2 | * Copyright (C) 2007 Oracle. All rights reserved. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public | |
6 | * License v2 as published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
11 | * General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public | |
14 | * License along with this program; if not, write to the | |
15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
16 | * Boston, MA 021110-1307, USA. | |
17 | */ | |
18 | ||
a6b6e75e | 19 | #include <linux/sched.h> |
eb60ceac CM |
20 | #include "ctree.h" |
21 | #include "disk-io.h" | |
7f5c1516 | 22 | #include "transaction.h" |
5f39d397 | 23 | #include "print-tree.h" |
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 | inline void btrfs_init_path(struct btrfs_path *p) |
2c90e5d6 | 42 | { |
df24a2b9 | 43 | memset(p, 0, sizeof(*p)); |
2c90e5d6 CM |
44 | } |
45 | ||
df24a2b9 | 46 | struct btrfs_path *btrfs_alloc_path(void) |
2c90e5d6 | 47 | { |
df24a2b9 CM |
48 | struct btrfs_path *path; |
49 | path = kmem_cache_alloc(btrfs_path_cachep, GFP_NOFS); | |
2cc58cf2 | 50 | if (path) { |
df24a2b9 | 51 | btrfs_init_path(path); |
2cc58cf2 CM |
52 | path->reada = 1; |
53 | } | |
df24a2b9 | 54 | return path; |
2c90e5d6 CM |
55 | } |
56 | ||
df24a2b9 | 57 | void btrfs_free_path(struct btrfs_path *p) |
be0e5c09 | 58 | { |
df24a2b9 CM |
59 | btrfs_release_path(NULL, p); |
60 | kmem_cache_free(btrfs_path_cachep, p); | |
be0e5c09 CM |
61 | } |
62 | ||
e02119d5 | 63 | void noinline btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p) |
eb60ceac CM |
64 | { |
65 | int i; | |
a2135011 | 66 | |
234b63a0 | 67 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
3f157a2f | 68 | p->slots[i] = 0; |
eb60ceac | 69 | if (!p->nodes[i]) |
925baedd CM |
70 | continue; |
71 | if (p->locks[i]) { | |
72 | btrfs_tree_unlock(p->nodes[i]); | |
73 | p->locks[i] = 0; | |
74 | } | |
5f39d397 | 75 | free_extent_buffer(p->nodes[i]); |
3f157a2f | 76 | p->nodes[i] = NULL; |
eb60ceac CM |
77 | } |
78 | } | |
79 | ||
925baedd CM |
80 | struct extent_buffer *btrfs_root_node(struct btrfs_root *root) |
81 | { | |
82 | struct extent_buffer *eb; | |
83 | spin_lock(&root->node_lock); | |
84 | eb = root->node; | |
85 | extent_buffer_get(eb); | |
86 | spin_unlock(&root->node_lock); | |
87 | return eb; | |
88 | } | |
89 | ||
90 | struct extent_buffer *btrfs_lock_root_node(struct btrfs_root *root) | |
91 | { | |
92 | struct extent_buffer *eb; | |
93 | ||
94 | while(1) { | |
95 | eb = btrfs_root_node(root); | |
96 | btrfs_tree_lock(eb); | |
97 | ||
98 | spin_lock(&root->node_lock); | |
99 | if (eb == root->node) { | |
100 | spin_unlock(&root->node_lock); | |
101 | break; | |
102 | } | |
103 | spin_unlock(&root->node_lock); | |
104 | ||
105 | btrfs_tree_unlock(eb); | |
106 | free_extent_buffer(eb); | |
107 | } | |
108 | return eb; | |
109 | } | |
110 | ||
0b86a832 CM |
111 | static void add_root_to_dirty_list(struct btrfs_root *root) |
112 | { | |
113 | if (root->track_dirty && list_empty(&root->dirty_list)) { | |
114 | list_add(&root->dirty_list, | |
115 | &root->fs_info->dirty_cowonly_roots); | |
116 | } | |
117 | } | |
118 | ||
be20aa9d CM |
119 | int btrfs_copy_root(struct btrfs_trans_handle *trans, |
120 | struct btrfs_root *root, | |
121 | struct extent_buffer *buf, | |
122 | struct extent_buffer **cow_ret, u64 new_root_objectid) | |
123 | { | |
124 | struct extent_buffer *cow; | |
125 | u32 nritems; | |
126 | int ret = 0; | |
127 | int level; | |
128 | struct btrfs_key first_key; | |
4aec2b52 | 129 | struct btrfs_root *new_root; |
be20aa9d | 130 | |
4aec2b52 CM |
131 | new_root = kmalloc(sizeof(*new_root), GFP_NOFS); |
132 | if (!new_root) | |
133 | return -ENOMEM; | |
134 | ||
135 | memcpy(new_root, root, sizeof(*new_root)); | |
136 | new_root->root_key.objectid = new_root_objectid; | |
be20aa9d CM |
137 | |
138 | WARN_ON(root->ref_cows && trans->transid != | |
139 | root->fs_info->running_transaction->transid); | |
140 | WARN_ON(root->ref_cows && trans->transid != root->last_trans); | |
141 | ||
142 | level = btrfs_header_level(buf); | |
143 | nritems = btrfs_header_nritems(buf); | |
144 | if (nritems) { | |
145 | if (level == 0) | |
146 | btrfs_item_key_to_cpu(buf, &first_key, 0); | |
147 | else | |
148 | btrfs_node_key_to_cpu(buf, &first_key, 0); | |
149 | } else { | |
150 | first_key.objectid = 0; | |
151 | } | |
925baedd | 152 | cow = btrfs_alloc_free_block(trans, new_root, buf->len, |
be20aa9d CM |
153 | new_root_objectid, |
154 | trans->transid, first_key.objectid, | |
155 | level, buf->start, 0); | |
4aec2b52 CM |
156 | if (IS_ERR(cow)) { |
157 | kfree(new_root); | |
be20aa9d | 158 | return PTR_ERR(cow); |
4aec2b52 | 159 | } |
be20aa9d CM |
160 | |
161 | copy_extent_buffer(cow, buf, 0, 0, cow->len); | |
162 | btrfs_set_header_bytenr(cow, cow->start); | |
163 | btrfs_set_header_generation(cow, trans->transid); | |
164 | btrfs_set_header_owner(cow, new_root_objectid); | |
63b10fc4 | 165 | btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN); |
be20aa9d CM |
166 | |
167 | WARN_ON(btrfs_header_generation(buf) > trans->transid); | |
31153d81 | 168 | ret = btrfs_inc_ref(trans, new_root, buf, 0); |
4aec2b52 CM |
169 | kfree(new_root); |
170 | ||
be20aa9d CM |
171 | if (ret) |
172 | return ret; | |
173 | ||
174 | btrfs_mark_buffer_dirty(cow); | |
175 | *cow_ret = cow; | |
176 | return 0; | |
177 | } | |
178 | ||
e02119d5 | 179 | int noinline __btrfs_cow_block(struct btrfs_trans_handle *trans, |
5f39d397 CM |
180 | struct btrfs_root *root, |
181 | struct extent_buffer *buf, | |
182 | struct extent_buffer *parent, int parent_slot, | |
183 | struct extent_buffer **cow_ret, | |
65b51a00 CM |
184 | u64 search_start, u64 empty_size, |
185 | u64 prealloc_dest) | |
02217ed2 | 186 | { |
7bb86316 | 187 | u64 root_gen; |
5f39d397 | 188 | struct extent_buffer *cow; |
7bb86316 | 189 | u32 nritems; |
6702ed49 CM |
190 | int ret = 0; |
191 | int different_trans = 0; | |
7bb86316 | 192 | int level; |
925baedd | 193 | int unlock_orig = 0; |
7bb86316 CM |
194 | struct btrfs_key first_key; |
195 | ||
925baedd CM |
196 | if (*cow_ret == buf) |
197 | unlock_orig = 1; | |
198 | ||
199 | WARN_ON(!btrfs_tree_locked(buf)); | |
200 | ||
7bb86316 CM |
201 | if (root->ref_cows) { |
202 | root_gen = trans->transid; | |
203 | } else { | |
204 | root_gen = 0; | |
205 | } | |
7bb86316 CM |
206 | WARN_ON(root->ref_cows && trans->transid != |
207 | root->fs_info->running_transaction->transid); | |
6702ed49 | 208 | WARN_ON(root->ref_cows && trans->transid != root->last_trans); |
5f39d397 | 209 | |
7bb86316 CM |
210 | level = btrfs_header_level(buf); |
211 | nritems = btrfs_header_nritems(buf); | |
212 | if (nritems) { | |
213 | if (level == 0) | |
214 | btrfs_item_key_to_cpu(buf, &first_key, 0); | |
215 | else | |
216 | btrfs_node_key_to_cpu(buf, &first_key, 0); | |
217 | } else { | |
218 | first_key.objectid = 0; | |
219 | } | |
65b51a00 CM |
220 | if (prealloc_dest) { |
221 | struct btrfs_key ins; | |
222 | ||
223 | ins.objectid = prealloc_dest; | |
224 | ins.offset = buf->len; | |
225 | ins.type = BTRFS_EXTENT_ITEM_KEY; | |
226 | ||
227 | ret = btrfs_alloc_reserved_extent(trans, root, | |
228 | root->root_key.objectid, | |
229 | root_gen, level, | |
230 | first_key.objectid, | |
231 | &ins); | |
232 | BUG_ON(ret); | |
233 | cow = btrfs_init_new_buffer(trans, root, prealloc_dest, | |
234 | buf->len); | |
235 | } else { | |
236 | cow = btrfs_alloc_free_block(trans, root, buf->len, | |
237 | root->root_key.objectid, | |
238 | root_gen, first_key.objectid, | |
239 | level, search_start, empty_size); | |
240 | } | |
54aa1f4d CM |
241 | if (IS_ERR(cow)) |
242 | return PTR_ERR(cow); | |
6702ed49 | 243 | |
5f39d397 | 244 | copy_extent_buffer(cow, buf, 0, 0, cow->len); |
db94535d | 245 | btrfs_set_header_bytenr(cow, cow->start); |
5f39d397 CM |
246 | btrfs_set_header_generation(cow, trans->transid); |
247 | btrfs_set_header_owner(cow, root->root_key.objectid); | |
63b10fc4 | 248 | btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN); |
6702ed49 | 249 | |
5f39d397 CM |
250 | WARN_ON(btrfs_header_generation(buf) > trans->transid); |
251 | if (btrfs_header_generation(buf) != trans->transid) { | |
6702ed49 | 252 | different_trans = 1; |
31153d81 | 253 | ret = btrfs_inc_ref(trans, root, buf, 1); |
6702ed49 CM |
254 | if (ret) |
255 | return ret; | |
256 | } else { | |
6702ed49 CM |
257 | clean_tree_block(trans, root, buf); |
258 | } | |
259 | ||
02217ed2 | 260 | if (buf == root->node) { |
925baedd | 261 | WARN_ON(parent && parent != buf); |
7bb86316 | 262 | root_gen = btrfs_header_generation(buf); |
925baedd CM |
263 | |
264 | spin_lock(&root->node_lock); | |
02217ed2 | 265 | root->node = cow; |
5f39d397 | 266 | extent_buffer_get(cow); |
925baedd CM |
267 | spin_unlock(&root->node_lock); |
268 | ||
2c90e5d6 | 269 | if (buf != root->commit_root) { |
db94535d | 270 | btrfs_free_extent(trans, root, buf->start, |
7bb86316 CM |
271 | buf->len, root->root_key.objectid, |
272 | root_gen, 0, 0, 1); | |
2c90e5d6 | 273 | } |
5f39d397 | 274 | free_extent_buffer(buf); |
0b86a832 | 275 | add_root_to_dirty_list(root); |
02217ed2 | 276 | } else { |
7bb86316 | 277 | root_gen = btrfs_header_generation(parent); |
5f39d397 | 278 | btrfs_set_node_blockptr(parent, parent_slot, |
db94535d | 279 | cow->start); |
74493f7a CM |
280 | WARN_ON(trans->transid == 0); |
281 | btrfs_set_node_ptr_generation(parent, parent_slot, | |
282 | trans->transid); | |
d6025579 | 283 | btrfs_mark_buffer_dirty(parent); |
5f39d397 | 284 | WARN_ON(btrfs_header_generation(parent) != trans->transid); |
7bb86316 CM |
285 | btrfs_free_extent(trans, root, buf->start, buf->len, |
286 | btrfs_header_owner(parent), root_gen, | |
287 | 0, 0, 1); | |
02217ed2 | 288 | } |
925baedd CM |
289 | if (unlock_orig) |
290 | btrfs_tree_unlock(buf); | |
5f39d397 | 291 | free_extent_buffer(buf); |
ccd467d6 | 292 | btrfs_mark_buffer_dirty(cow); |
2c90e5d6 | 293 | *cow_ret = cow; |
02217ed2 CM |
294 | return 0; |
295 | } | |
296 | ||
e02119d5 | 297 | int noinline btrfs_cow_block(struct btrfs_trans_handle *trans, |
5f39d397 CM |
298 | struct btrfs_root *root, struct extent_buffer *buf, |
299 | struct extent_buffer *parent, int parent_slot, | |
65b51a00 | 300 | struct extent_buffer **cow_ret, u64 prealloc_dest) |
6702ed49 CM |
301 | { |
302 | u64 search_start; | |
dc17ff8f | 303 | u64 header_trans; |
f510cfec | 304 | int ret; |
dc17ff8f | 305 | |
6702ed49 CM |
306 | if (trans->transaction != root->fs_info->running_transaction) { |
307 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
308 | root->fs_info->running_transaction->transid); | |
309 | WARN_ON(1); | |
310 | } | |
311 | if (trans->transid != root->fs_info->generation) { | |
312 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
313 | root->fs_info->generation); | |
314 | WARN_ON(1); | |
315 | } | |
dc17ff8f CM |
316 | |
317 | header_trans = btrfs_header_generation(buf); | |
63b10fc4 CM |
318 | spin_lock(&root->fs_info->hash_lock); |
319 | if (header_trans == trans->transid && | |
320 | !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) { | |
6702ed49 | 321 | *cow_ret = buf; |
63b10fc4 | 322 | spin_unlock(&root->fs_info->hash_lock); |
65b51a00 | 323 | WARN_ON(prealloc_dest); |
6702ed49 CM |
324 | return 0; |
325 | } | |
63b10fc4 | 326 | spin_unlock(&root->fs_info->hash_lock); |
0b86a832 | 327 | search_start = buf->start & ~((u64)(1024 * 1024 * 1024) - 1); |
f510cfec | 328 | ret = __btrfs_cow_block(trans, root, buf, parent, |
65b51a00 CM |
329 | parent_slot, cow_ret, search_start, 0, |
330 | prealloc_dest); | |
f510cfec | 331 | return ret; |
6702ed49 CM |
332 | } |
333 | ||
6b80053d | 334 | static int close_blocks(u64 blocknr, u64 other, u32 blocksize) |
6702ed49 | 335 | { |
6b80053d | 336 | if (blocknr < other && other - (blocknr + blocksize) < 32768) |
6702ed49 | 337 | return 1; |
6b80053d | 338 | if (blocknr > other && blocknr - (other + blocksize) < 32768) |
6702ed49 CM |
339 | return 1; |
340 | return 0; | |
341 | } | |
342 | ||
081e9573 CM |
343 | /* |
344 | * compare two keys in a memcmp fashion | |
345 | */ | |
346 | static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2) | |
347 | { | |
348 | struct btrfs_key k1; | |
349 | ||
350 | btrfs_disk_key_to_cpu(&k1, disk); | |
351 | ||
352 | if (k1.objectid > k2->objectid) | |
353 | return 1; | |
354 | if (k1.objectid < k2->objectid) | |
355 | return -1; | |
356 | if (k1.type > k2->type) | |
357 | return 1; | |
358 | if (k1.type < k2->type) | |
359 | return -1; | |
360 | if (k1.offset > k2->offset) | |
361 | return 1; | |
362 | if (k1.offset < k2->offset) | |
363 | return -1; | |
364 | return 0; | |
365 | } | |
366 | ||
367 | ||
6702ed49 | 368 | int btrfs_realloc_node(struct btrfs_trans_handle *trans, |
5f39d397 | 369 | struct btrfs_root *root, struct extent_buffer *parent, |
a6b6e75e CM |
370 | int start_slot, int cache_only, u64 *last_ret, |
371 | struct btrfs_key *progress) | |
6702ed49 | 372 | { |
6b80053d | 373 | struct extent_buffer *cur; |
6702ed49 | 374 | u64 blocknr; |
ca7a79ad | 375 | u64 gen; |
e9d0b13b CM |
376 | u64 search_start = *last_ret; |
377 | u64 last_block = 0; | |
6702ed49 CM |
378 | u64 other; |
379 | u32 parent_nritems; | |
6702ed49 CM |
380 | int end_slot; |
381 | int i; | |
382 | int err = 0; | |
f2183bde | 383 | int parent_level; |
6b80053d CM |
384 | int uptodate; |
385 | u32 blocksize; | |
081e9573 CM |
386 | int progress_passed = 0; |
387 | struct btrfs_disk_key disk_key; | |
6702ed49 | 388 | |
5708b959 CM |
389 | parent_level = btrfs_header_level(parent); |
390 | if (cache_only && parent_level != 1) | |
391 | return 0; | |
392 | ||
6702ed49 CM |
393 | if (trans->transaction != root->fs_info->running_transaction) { |
394 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
395 | root->fs_info->running_transaction->transid); | |
396 | WARN_ON(1); | |
397 | } | |
398 | if (trans->transid != root->fs_info->generation) { | |
399 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
400 | root->fs_info->generation); | |
401 | WARN_ON(1); | |
402 | } | |
86479a04 | 403 | |
6b80053d | 404 | parent_nritems = btrfs_header_nritems(parent); |
6b80053d | 405 | blocksize = btrfs_level_size(root, parent_level - 1); |
6702ed49 CM |
406 | end_slot = parent_nritems; |
407 | ||
408 | if (parent_nritems == 1) | |
409 | return 0; | |
410 | ||
411 | for (i = start_slot; i < end_slot; i++) { | |
412 | int close = 1; | |
a6b6e75e | 413 | |
5708b959 CM |
414 | if (!parent->map_token) { |
415 | map_extent_buffer(parent, | |
416 | btrfs_node_key_ptr_offset(i), | |
417 | sizeof(struct btrfs_key_ptr), | |
418 | &parent->map_token, &parent->kaddr, | |
419 | &parent->map_start, &parent->map_len, | |
420 | KM_USER1); | |
421 | } | |
081e9573 CM |
422 | btrfs_node_key(parent, &disk_key, i); |
423 | if (!progress_passed && comp_keys(&disk_key, progress) < 0) | |
424 | continue; | |
425 | ||
426 | progress_passed = 1; | |
6b80053d | 427 | blocknr = btrfs_node_blockptr(parent, i); |
ca7a79ad | 428 | gen = btrfs_node_ptr_generation(parent, i); |
e9d0b13b CM |
429 | if (last_block == 0) |
430 | last_block = blocknr; | |
5708b959 | 431 | |
6702ed49 | 432 | if (i > 0) { |
6b80053d CM |
433 | other = btrfs_node_blockptr(parent, i - 1); |
434 | close = close_blocks(blocknr, other, blocksize); | |
6702ed49 | 435 | } |
0ef3e66b | 436 | if (!close && i < end_slot - 2) { |
6b80053d CM |
437 | other = btrfs_node_blockptr(parent, i + 1); |
438 | close = close_blocks(blocknr, other, blocksize); | |
6702ed49 | 439 | } |
e9d0b13b CM |
440 | if (close) { |
441 | last_block = blocknr; | |
6702ed49 | 442 | continue; |
e9d0b13b | 443 | } |
5708b959 CM |
444 | if (parent->map_token) { |
445 | unmap_extent_buffer(parent, parent->map_token, | |
446 | KM_USER1); | |
447 | parent->map_token = NULL; | |
448 | } | |
6702ed49 | 449 | |
6b80053d CM |
450 | cur = btrfs_find_tree_block(root, blocknr, blocksize); |
451 | if (cur) | |
1259ab75 | 452 | uptodate = btrfs_buffer_uptodate(cur, gen); |
6b80053d CM |
453 | else |
454 | uptodate = 0; | |
5708b959 | 455 | if (!cur || !uptodate) { |
6702ed49 | 456 | if (cache_only) { |
6b80053d | 457 | free_extent_buffer(cur); |
6702ed49 CM |
458 | continue; |
459 | } | |
6b80053d CM |
460 | if (!cur) { |
461 | cur = read_tree_block(root, blocknr, | |
ca7a79ad | 462 | blocksize, gen); |
6b80053d | 463 | } else if (!uptodate) { |
ca7a79ad | 464 | btrfs_read_buffer(cur, gen); |
f2183bde | 465 | } |
6702ed49 | 466 | } |
e9d0b13b | 467 | if (search_start == 0) |
6b80053d | 468 | search_start = last_block; |
e9d0b13b | 469 | |
e7a84565 | 470 | btrfs_tree_lock(cur); |
6b80053d | 471 | err = __btrfs_cow_block(trans, root, cur, parent, i, |
e7a84565 | 472 | &cur, search_start, |
6b80053d | 473 | min(16 * blocksize, |
65b51a00 | 474 | (end_slot - i) * blocksize), 0); |
252c38f0 | 475 | if (err) { |
e7a84565 | 476 | btrfs_tree_unlock(cur); |
6b80053d | 477 | free_extent_buffer(cur); |
6702ed49 | 478 | break; |
252c38f0 | 479 | } |
e7a84565 CM |
480 | search_start = cur->start; |
481 | last_block = cur->start; | |
f2183bde | 482 | *last_ret = search_start; |
e7a84565 CM |
483 | btrfs_tree_unlock(cur); |
484 | free_extent_buffer(cur); | |
6702ed49 | 485 | } |
5708b959 CM |
486 | if (parent->map_token) { |
487 | unmap_extent_buffer(parent, parent->map_token, | |
488 | KM_USER1); | |
489 | parent->map_token = NULL; | |
490 | } | |
6702ed49 CM |
491 | return err; |
492 | } | |
493 | ||
74123bd7 CM |
494 | /* |
495 | * The leaf data grows from end-to-front in the node. | |
496 | * this returns the address of the start of the last item, | |
497 | * which is the stop of the leaf data stack | |
498 | */ | |
123abc88 | 499 | static inline unsigned int leaf_data_end(struct btrfs_root *root, |
5f39d397 | 500 | struct extent_buffer *leaf) |
be0e5c09 | 501 | { |
5f39d397 | 502 | u32 nr = btrfs_header_nritems(leaf); |
be0e5c09 | 503 | if (nr == 0) |
123abc88 | 504 | return BTRFS_LEAF_DATA_SIZE(root); |
5f39d397 | 505 | return btrfs_item_offset_nr(leaf, nr - 1); |
be0e5c09 CM |
506 | } |
507 | ||
123abc88 CM |
508 | static int check_node(struct btrfs_root *root, struct btrfs_path *path, |
509 | int level) | |
aa5d6bed | 510 | { |
5f39d397 CM |
511 | struct extent_buffer *parent = NULL; |
512 | struct extent_buffer *node = path->nodes[level]; | |
513 | struct btrfs_disk_key parent_key; | |
514 | struct btrfs_disk_key node_key; | |
aa5d6bed | 515 | int parent_slot; |
8d7be552 CM |
516 | int slot; |
517 | struct btrfs_key cpukey; | |
5f39d397 | 518 | u32 nritems = btrfs_header_nritems(node); |
aa5d6bed CM |
519 | |
520 | if (path->nodes[level + 1]) | |
5f39d397 | 521 | parent = path->nodes[level + 1]; |
a1f39630 | 522 | |
8d7be552 | 523 | slot = path->slots[level]; |
7518a238 CM |
524 | BUG_ON(nritems == 0); |
525 | if (parent) { | |
a1f39630 | 526 | parent_slot = path->slots[level + 1]; |
5f39d397 CM |
527 | btrfs_node_key(parent, &parent_key, parent_slot); |
528 | btrfs_node_key(node, &node_key, 0); | |
529 | BUG_ON(memcmp(&parent_key, &node_key, | |
e2fa7227 | 530 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 531 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
db94535d | 532 | btrfs_header_bytenr(node)); |
aa5d6bed | 533 | } |
123abc88 | 534 | BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root)); |
8d7be552 | 535 | if (slot != 0) { |
5f39d397 CM |
536 | btrfs_node_key_to_cpu(node, &cpukey, slot - 1); |
537 | btrfs_node_key(node, &node_key, slot); | |
538 | BUG_ON(comp_keys(&node_key, &cpukey) <= 0); | |
8d7be552 CM |
539 | } |
540 | if (slot < nritems - 1) { | |
5f39d397 CM |
541 | btrfs_node_key_to_cpu(node, &cpukey, slot + 1); |
542 | btrfs_node_key(node, &node_key, slot); | |
543 | BUG_ON(comp_keys(&node_key, &cpukey) >= 0); | |
aa5d6bed CM |
544 | } |
545 | return 0; | |
546 | } | |
547 | ||
123abc88 CM |
548 | static int check_leaf(struct btrfs_root *root, struct btrfs_path *path, |
549 | int level) | |
aa5d6bed | 550 | { |
5f39d397 CM |
551 | struct extent_buffer *leaf = path->nodes[level]; |
552 | struct extent_buffer *parent = NULL; | |
aa5d6bed | 553 | int parent_slot; |
8d7be552 | 554 | struct btrfs_key cpukey; |
5f39d397 CM |
555 | struct btrfs_disk_key parent_key; |
556 | struct btrfs_disk_key leaf_key; | |
557 | int slot = path->slots[0]; | |
8d7be552 | 558 | |
5f39d397 | 559 | u32 nritems = btrfs_header_nritems(leaf); |
aa5d6bed CM |
560 | |
561 | if (path->nodes[level + 1]) | |
5f39d397 | 562 | parent = path->nodes[level + 1]; |
7518a238 CM |
563 | |
564 | if (nritems == 0) | |
565 | return 0; | |
566 | ||
567 | if (parent) { | |
a1f39630 | 568 | parent_slot = path->slots[level + 1]; |
5f39d397 CM |
569 | btrfs_node_key(parent, &parent_key, parent_slot); |
570 | btrfs_item_key(leaf, &leaf_key, 0); | |
6702ed49 | 571 | |
5f39d397 | 572 | BUG_ON(memcmp(&parent_key, &leaf_key, |
e2fa7227 | 573 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 574 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
db94535d | 575 | btrfs_header_bytenr(leaf)); |
5f39d397 CM |
576 | } |
577 | #if 0 | |
578 | for (i = 0; nritems > 1 && i < nritems - 2; i++) { | |
579 | btrfs_item_key_to_cpu(leaf, &cpukey, i + 1); | |
580 | btrfs_item_key(leaf, &leaf_key, i); | |
581 | if (comp_keys(&leaf_key, &cpukey) >= 0) { | |
582 | btrfs_print_leaf(root, leaf); | |
583 | printk("slot %d offset bad key\n", i); | |
584 | BUG_ON(1); | |
585 | } | |
586 | if (btrfs_item_offset_nr(leaf, i) != | |
587 | btrfs_item_end_nr(leaf, i + 1)) { | |
588 | btrfs_print_leaf(root, leaf); | |
589 | printk("slot %d offset bad\n", i); | |
590 | BUG_ON(1); | |
591 | } | |
592 | if (i == 0) { | |
593 | if (btrfs_item_offset_nr(leaf, i) + | |
594 | btrfs_item_size_nr(leaf, i) != | |
595 | BTRFS_LEAF_DATA_SIZE(root)) { | |
596 | btrfs_print_leaf(root, leaf); | |
597 | printk("slot %d first offset bad\n", i); | |
598 | BUG_ON(1); | |
599 | } | |
600 | } | |
aa5d6bed | 601 | } |
5f39d397 CM |
602 | if (nritems > 0) { |
603 | if (btrfs_item_size_nr(leaf, nritems - 1) > 4096) { | |
604 | btrfs_print_leaf(root, leaf); | |
605 | printk("slot %d bad size \n", nritems - 1); | |
606 | BUG_ON(1); | |
607 | } | |
608 | } | |
609 | #endif | |
610 | if (slot != 0 && slot < nritems - 1) { | |
611 | btrfs_item_key(leaf, &leaf_key, slot); | |
612 | btrfs_item_key_to_cpu(leaf, &cpukey, slot - 1); | |
613 | if (comp_keys(&leaf_key, &cpukey) <= 0) { | |
614 | btrfs_print_leaf(root, leaf); | |
615 | printk("slot %d offset bad key\n", slot); | |
616 | BUG_ON(1); | |
617 | } | |
618 | if (btrfs_item_offset_nr(leaf, slot - 1) != | |
619 | btrfs_item_end_nr(leaf, slot)) { | |
620 | btrfs_print_leaf(root, leaf); | |
621 | printk("slot %d offset bad\n", slot); | |
622 | BUG_ON(1); | |
623 | } | |
8d7be552 CM |
624 | } |
625 | if (slot < nritems - 1) { | |
5f39d397 CM |
626 | btrfs_item_key(leaf, &leaf_key, slot); |
627 | btrfs_item_key_to_cpu(leaf, &cpukey, slot + 1); | |
628 | BUG_ON(comp_keys(&leaf_key, &cpukey) >= 0); | |
629 | if (btrfs_item_offset_nr(leaf, slot) != | |
630 | btrfs_item_end_nr(leaf, slot + 1)) { | |
631 | btrfs_print_leaf(root, leaf); | |
632 | printk("slot %d offset bad\n", slot); | |
633 | BUG_ON(1); | |
634 | } | |
aa5d6bed | 635 | } |
5f39d397 CM |
636 | BUG_ON(btrfs_item_offset_nr(leaf, 0) + |
637 | btrfs_item_size_nr(leaf, 0) != BTRFS_LEAF_DATA_SIZE(root)); | |
aa5d6bed CM |
638 | return 0; |
639 | } | |
640 | ||
98ed5174 CM |
641 | static int noinline check_block(struct btrfs_root *root, |
642 | struct btrfs_path *path, int level) | |
aa5d6bed | 643 | { |
f188591e | 644 | u64 found_start; |
85d824c4 | 645 | return 0; |
f188591e CM |
646 | if (btrfs_header_level(path->nodes[level]) != level) |
647 | printk("warning: bad level %Lu wanted %d found %d\n", | |
648 | path->nodes[level]->start, level, | |
649 | btrfs_header_level(path->nodes[level])); | |
650 | found_start = btrfs_header_bytenr(path->nodes[level]); | |
651 | if (found_start != path->nodes[level]->start) { | |
652 | printk("warning: bad bytentr %Lu found %Lu\n", | |
653 | path->nodes[level]->start, found_start); | |
654 | } | |
db94535d | 655 | #if 0 |
5f39d397 | 656 | struct extent_buffer *buf = path->nodes[level]; |
5f39d397 | 657 | |
479965d6 CM |
658 | if (memcmp_extent_buffer(buf, root->fs_info->fsid, |
659 | (unsigned long)btrfs_header_fsid(buf), | |
660 | BTRFS_FSID_SIZE)) { | |
5f39d397 | 661 | printk("warning bad block %Lu\n", buf->start); |
db94535d | 662 | return 1; |
5f39d397 | 663 | } |
db94535d | 664 | #endif |
aa5d6bed | 665 | if (level == 0) |
123abc88 CM |
666 | return check_leaf(root, path, level); |
667 | return check_node(root, path, level); | |
aa5d6bed CM |
668 | } |
669 | ||
74123bd7 | 670 | /* |
5f39d397 CM |
671 | * search for key in the extent_buffer. The items start at offset p, |
672 | * and they are item_size apart. There are 'max' items in p. | |
673 | * | |
74123bd7 CM |
674 | * the slot in the array is returned via slot, and it points to |
675 | * the place where you would insert key if it is not found in | |
676 | * the array. | |
677 | * | |
678 | * slot may point to max if the key is bigger than all of the keys | |
679 | */ | |
e02119d5 CM |
680 | static noinline int generic_bin_search(struct extent_buffer *eb, |
681 | unsigned long p, | |
682 | int item_size, struct btrfs_key *key, | |
683 | int max, int *slot) | |
be0e5c09 CM |
684 | { |
685 | int low = 0; | |
686 | int high = max; | |
687 | int mid; | |
688 | int ret; | |
479965d6 | 689 | struct btrfs_disk_key *tmp = NULL; |
5f39d397 CM |
690 | struct btrfs_disk_key unaligned; |
691 | unsigned long offset; | |
692 | char *map_token = NULL; | |
693 | char *kaddr = NULL; | |
694 | unsigned long map_start = 0; | |
695 | unsigned long map_len = 0; | |
479965d6 | 696 | int err; |
be0e5c09 CM |
697 | |
698 | while(low < high) { | |
699 | mid = (low + high) / 2; | |
5f39d397 CM |
700 | offset = p + mid * item_size; |
701 | ||
702 | if (!map_token || offset < map_start || | |
703 | (offset + sizeof(struct btrfs_disk_key)) > | |
704 | map_start + map_len) { | |
479965d6 | 705 | if (map_token) { |
5f39d397 | 706 | unmap_extent_buffer(eb, map_token, KM_USER0); |
479965d6 CM |
707 | map_token = NULL; |
708 | } | |
709 | err = map_extent_buffer(eb, offset, | |
710 | sizeof(struct btrfs_disk_key), | |
711 | &map_token, &kaddr, | |
712 | &map_start, &map_len, KM_USER0); | |
713 | ||
714 | if (!err) { | |
715 | tmp = (struct btrfs_disk_key *)(kaddr + offset - | |
716 | map_start); | |
717 | } else { | |
718 | read_extent_buffer(eb, &unaligned, | |
719 | offset, sizeof(unaligned)); | |
720 | tmp = &unaligned; | |
721 | } | |
5f39d397 | 722 | |
5f39d397 CM |
723 | } else { |
724 | tmp = (struct btrfs_disk_key *)(kaddr + offset - | |
725 | map_start); | |
726 | } | |
be0e5c09 CM |
727 | ret = comp_keys(tmp, key); |
728 | ||
729 | if (ret < 0) | |
730 | low = mid + 1; | |
731 | else if (ret > 0) | |
732 | high = mid; | |
733 | else { | |
734 | *slot = mid; | |
479965d6 CM |
735 | if (map_token) |
736 | unmap_extent_buffer(eb, map_token, KM_USER0); | |
be0e5c09 CM |
737 | return 0; |
738 | } | |
739 | } | |
740 | *slot = low; | |
5f39d397 CM |
741 | if (map_token) |
742 | unmap_extent_buffer(eb, map_token, KM_USER0); | |
be0e5c09 CM |
743 | return 1; |
744 | } | |
745 | ||
97571fd0 CM |
746 | /* |
747 | * simple bin_search frontend that does the right thing for | |
748 | * leaves vs nodes | |
749 | */ | |
5f39d397 CM |
750 | static int bin_search(struct extent_buffer *eb, struct btrfs_key *key, |
751 | int level, int *slot) | |
be0e5c09 | 752 | { |
5f39d397 CM |
753 | if (level == 0) { |
754 | return generic_bin_search(eb, | |
755 | offsetof(struct btrfs_leaf, items), | |
0783fcfc | 756 | sizeof(struct btrfs_item), |
5f39d397 | 757 | key, btrfs_header_nritems(eb), |
7518a238 | 758 | slot); |
be0e5c09 | 759 | } else { |
5f39d397 CM |
760 | return generic_bin_search(eb, |
761 | offsetof(struct btrfs_node, ptrs), | |
123abc88 | 762 | sizeof(struct btrfs_key_ptr), |
5f39d397 | 763 | key, btrfs_header_nritems(eb), |
7518a238 | 764 | slot); |
be0e5c09 CM |
765 | } |
766 | return -1; | |
767 | } | |
768 | ||
e02119d5 | 769 | static noinline struct extent_buffer *read_node_slot(struct btrfs_root *root, |
5f39d397 | 770 | struct extent_buffer *parent, int slot) |
bb803951 | 771 | { |
ca7a79ad | 772 | int level = btrfs_header_level(parent); |
bb803951 CM |
773 | if (slot < 0) |
774 | return NULL; | |
5f39d397 | 775 | if (slot >= btrfs_header_nritems(parent)) |
bb803951 | 776 | return NULL; |
ca7a79ad CM |
777 | |
778 | BUG_ON(level == 0); | |
779 | ||
db94535d | 780 | return read_tree_block(root, btrfs_node_blockptr(parent, slot), |
ca7a79ad CM |
781 | btrfs_level_size(root, level - 1), |
782 | btrfs_node_ptr_generation(parent, slot)); | |
bb803951 CM |
783 | } |
784 | ||
e02119d5 | 785 | static noinline int balance_level(struct btrfs_trans_handle *trans, |
98ed5174 CM |
786 | struct btrfs_root *root, |
787 | struct btrfs_path *path, int level) | |
bb803951 | 788 | { |
5f39d397 CM |
789 | struct extent_buffer *right = NULL; |
790 | struct extent_buffer *mid; | |
791 | struct extent_buffer *left = NULL; | |
792 | struct extent_buffer *parent = NULL; | |
bb803951 CM |
793 | int ret = 0; |
794 | int wret; | |
795 | int pslot; | |
bb803951 | 796 | int orig_slot = path->slots[level]; |
54aa1f4d | 797 | int err_on_enospc = 0; |
79f95c82 | 798 | u64 orig_ptr; |
bb803951 CM |
799 | |
800 | if (level == 0) | |
801 | return 0; | |
802 | ||
5f39d397 | 803 | mid = path->nodes[level]; |
925baedd | 804 | WARN_ON(!path->locks[level]); |
7bb86316 CM |
805 | WARN_ON(btrfs_header_generation(mid) != trans->transid); |
806 | ||
1d4f8a0c | 807 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
79f95c82 | 808 | |
234b63a0 | 809 | if (level < BTRFS_MAX_LEVEL - 1) |
5f39d397 | 810 | parent = path->nodes[level + 1]; |
bb803951 CM |
811 | pslot = path->slots[level + 1]; |
812 | ||
40689478 CM |
813 | /* |
814 | * deal with the case where there is only one pointer in the root | |
815 | * by promoting the node below to a root | |
816 | */ | |
5f39d397 CM |
817 | if (!parent) { |
818 | struct extent_buffer *child; | |
bb803951 | 819 | |
5f39d397 | 820 | if (btrfs_header_nritems(mid) != 1) |
bb803951 CM |
821 | return 0; |
822 | ||
823 | /* promote the child to a root */ | |
5f39d397 | 824 | child = read_node_slot(root, mid, 0); |
925baedd | 825 | btrfs_tree_lock(child); |
bb803951 | 826 | BUG_ON(!child); |
65b51a00 | 827 | ret = btrfs_cow_block(trans, root, child, mid, 0, &child, 0); |
2f375ab9 Y |
828 | BUG_ON(ret); |
829 | ||
925baedd | 830 | spin_lock(&root->node_lock); |
bb803951 | 831 | root->node = child; |
925baedd CM |
832 | spin_unlock(&root->node_lock); |
833 | ||
0b86a832 | 834 | add_root_to_dirty_list(root); |
925baedd CM |
835 | btrfs_tree_unlock(child); |
836 | path->locks[level] = 0; | |
bb803951 | 837 | path->nodes[level] = NULL; |
5f39d397 | 838 | clean_tree_block(trans, root, mid); |
925baedd | 839 | btrfs_tree_unlock(mid); |
bb803951 | 840 | /* once for the path */ |
5f39d397 | 841 | free_extent_buffer(mid); |
7bb86316 CM |
842 | ret = btrfs_free_extent(trans, root, mid->start, mid->len, |
843 | root->root_key.objectid, | |
844 | btrfs_header_generation(mid), 0, 0, 1); | |
bb803951 | 845 | /* once for the root ptr */ |
5f39d397 | 846 | free_extent_buffer(mid); |
db94535d | 847 | return ret; |
bb803951 | 848 | } |
5f39d397 | 849 | if (btrfs_header_nritems(mid) > |
123abc88 | 850 | BTRFS_NODEPTRS_PER_BLOCK(root) / 4) |
bb803951 CM |
851 | return 0; |
852 | ||
5f39d397 | 853 | if (btrfs_header_nritems(mid) < 2) |
54aa1f4d CM |
854 | err_on_enospc = 1; |
855 | ||
5f39d397 CM |
856 | left = read_node_slot(root, parent, pslot - 1); |
857 | if (left) { | |
925baedd | 858 | btrfs_tree_lock(left); |
5f39d397 | 859 | wret = btrfs_cow_block(trans, root, left, |
65b51a00 | 860 | parent, pslot - 1, &left, 0); |
54aa1f4d CM |
861 | if (wret) { |
862 | ret = wret; | |
863 | goto enospc; | |
864 | } | |
2cc58cf2 | 865 | } |
5f39d397 CM |
866 | right = read_node_slot(root, parent, pslot + 1); |
867 | if (right) { | |
925baedd | 868 | btrfs_tree_lock(right); |
5f39d397 | 869 | wret = btrfs_cow_block(trans, root, right, |
65b51a00 | 870 | parent, pslot + 1, &right, 0); |
2cc58cf2 CM |
871 | if (wret) { |
872 | ret = wret; | |
873 | goto enospc; | |
874 | } | |
875 | } | |
876 | ||
877 | /* first, try to make some room in the middle buffer */ | |
5f39d397 CM |
878 | if (left) { |
879 | orig_slot += btrfs_header_nritems(left); | |
bce4eae9 | 880 | wret = push_node_left(trans, root, left, mid, 1); |
79f95c82 CM |
881 | if (wret < 0) |
882 | ret = wret; | |
5f39d397 | 883 | if (btrfs_header_nritems(mid) < 2) |
54aa1f4d | 884 | err_on_enospc = 1; |
bb803951 | 885 | } |
79f95c82 CM |
886 | |
887 | /* | |
888 | * then try to empty the right most buffer into the middle | |
889 | */ | |
5f39d397 | 890 | if (right) { |
971a1f66 | 891 | wret = push_node_left(trans, root, mid, right, 1); |
54aa1f4d | 892 | if (wret < 0 && wret != -ENOSPC) |
79f95c82 | 893 | ret = wret; |
5f39d397 | 894 | if (btrfs_header_nritems(right) == 0) { |
db94535d | 895 | u64 bytenr = right->start; |
7bb86316 | 896 | u64 generation = btrfs_header_generation(parent); |
db94535d CM |
897 | u32 blocksize = right->len; |
898 | ||
5f39d397 | 899 | clean_tree_block(trans, root, right); |
925baedd | 900 | btrfs_tree_unlock(right); |
5f39d397 | 901 | free_extent_buffer(right); |
bb803951 | 902 | right = NULL; |
e089f05c CM |
903 | wret = del_ptr(trans, root, path, level + 1, pslot + |
904 | 1); | |
bb803951 CM |
905 | if (wret) |
906 | ret = wret; | |
db94535d | 907 | wret = btrfs_free_extent(trans, root, bytenr, |
7bb86316 CM |
908 | blocksize, |
909 | btrfs_header_owner(parent), | |
910 | generation, 0, 0, 1); | |
bb803951 CM |
911 | if (wret) |
912 | ret = wret; | |
913 | } else { | |
5f39d397 CM |
914 | struct btrfs_disk_key right_key; |
915 | btrfs_node_key(right, &right_key, 0); | |
916 | btrfs_set_node_key(parent, &right_key, pslot + 1); | |
917 | btrfs_mark_buffer_dirty(parent); | |
bb803951 CM |
918 | } |
919 | } | |
5f39d397 | 920 | if (btrfs_header_nritems(mid) == 1) { |
79f95c82 CM |
921 | /* |
922 | * we're not allowed to leave a node with one item in the | |
923 | * tree during a delete. A deletion from lower in the tree | |
924 | * could try to delete the only pointer in this node. | |
925 | * So, pull some keys from the left. | |
926 | * There has to be a left pointer at this point because | |
927 | * otherwise we would have pulled some pointers from the | |
928 | * right | |
929 | */ | |
5f39d397 CM |
930 | BUG_ON(!left); |
931 | wret = balance_node_right(trans, root, mid, left); | |
54aa1f4d | 932 | if (wret < 0) { |
79f95c82 | 933 | ret = wret; |
54aa1f4d CM |
934 | goto enospc; |
935 | } | |
bce4eae9 CM |
936 | if (wret == 1) { |
937 | wret = push_node_left(trans, root, left, mid, 1); | |
938 | if (wret < 0) | |
939 | ret = wret; | |
940 | } | |
79f95c82 CM |
941 | BUG_ON(wret == 1); |
942 | } | |
5f39d397 | 943 | if (btrfs_header_nritems(mid) == 0) { |
79f95c82 | 944 | /* we've managed to empty the middle node, drop it */ |
7bb86316 | 945 | u64 root_gen = btrfs_header_generation(parent); |
db94535d CM |
946 | u64 bytenr = mid->start; |
947 | u32 blocksize = mid->len; | |
925baedd | 948 | |
5f39d397 | 949 | clean_tree_block(trans, root, mid); |
925baedd | 950 | btrfs_tree_unlock(mid); |
5f39d397 | 951 | free_extent_buffer(mid); |
bb803951 | 952 | mid = NULL; |
e089f05c | 953 | wret = del_ptr(trans, root, path, level + 1, pslot); |
bb803951 CM |
954 | if (wret) |
955 | ret = wret; | |
7bb86316 CM |
956 | wret = btrfs_free_extent(trans, root, bytenr, blocksize, |
957 | btrfs_header_owner(parent), | |
958 | root_gen, 0, 0, 1); | |
bb803951 CM |
959 | if (wret) |
960 | ret = wret; | |
79f95c82 CM |
961 | } else { |
962 | /* update the parent key to reflect our changes */ | |
5f39d397 CM |
963 | struct btrfs_disk_key mid_key; |
964 | btrfs_node_key(mid, &mid_key, 0); | |
965 | btrfs_set_node_key(parent, &mid_key, pslot); | |
966 | btrfs_mark_buffer_dirty(parent); | |
79f95c82 | 967 | } |
bb803951 | 968 | |
79f95c82 | 969 | /* update the path */ |
5f39d397 CM |
970 | if (left) { |
971 | if (btrfs_header_nritems(left) > orig_slot) { | |
972 | extent_buffer_get(left); | |
925baedd | 973 | /* left was locked after cow */ |
5f39d397 | 974 | path->nodes[level] = left; |
bb803951 CM |
975 | path->slots[level + 1] -= 1; |
976 | path->slots[level] = orig_slot; | |
925baedd CM |
977 | if (mid) { |
978 | btrfs_tree_unlock(mid); | |
5f39d397 | 979 | free_extent_buffer(mid); |
925baedd | 980 | } |
bb803951 | 981 | } else { |
5f39d397 | 982 | orig_slot -= btrfs_header_nritems(left); |
bb803951 CM |
983 | path->slots[level] = orig_slot; |
984 | } | |
985 | } | |
79f95c82 | 986 | /* double check we haven't messed things up */ |
123abc88 | 987 | check_block(root, path, level); |
e20d96d6 | 988 | if (orig_ptr != |
5f39d397 | 989 | btrfs_node_blockptr(path->nodes[level], path->slots[level])) |
79f95c82 | 990 | BUG(); |
54aa1f4d | 991 | enospc: |
925baedd CM |
992 | if (right) { |
993 | btrfs_tree_unlock(right); | |
5f39d397 | 994 | free_extent_buffer(right); |
925baedd CM |
995 | } |
996 | if (left) { | |
997 | if (path->nodes[level] != left) | |
998 | btrfs_tree_unlock(left); | |
5f39d397 | 999 | free_extent_buffer(left); |
925baedd | 1000 | } |
bb803951 CM |
1001 | return ret; |
1002 | } | |
1003 | ||
e66f709b | 1004 | /* returns zero if the push worked, non-zero otherwise */ |
98ed5174 CM |
1005 | static int noinline push_nodes_for_insert(struct btrfs_trans_handle *trans, |
1006 | struct btrfs_root *root, | |
1007 | struct btrfs_path *path, int level) | |
e66f709b | 1008 | { |
5f39d397 CM |
1009 | struct extent_buffer *right = NULL; |
1010 | struct extent_buffer *mid; | |
1011 | struct extent_buffer *left = NULL; | |
1012 | struct extent_buffer *parent = NULL; | |
e66f709b CM |
1013 | int ret = 0; |
1014 | int wret; | |
1015 | int pslot; | |
1016 | int orig_slot = path->slots[level]; | |
1017 | u64 orig_ptr; | |
1018 | ||
1019 | if (level == 0) | |
1020 | return 1; | |
1021 | ||
5f39d397 | 1022 | mid = path->nodes[level]; |
7bb86316 | 1023 | WARN_ON(btrfs_header_generation(mid) != trans->transid); |
e66f709b CM |
1024 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
1025 | ||
1026 | if (level < BTRFS_MAX_LEVEL - 1) | |
5f39d397 | 1027 | parent = path->nodes[level + 1]; |
e66f709b CM |
1028 | pslot = path->slots[level + 1]; |
1029 | ||
5f39d397 | 1030 | if (!parent) |
e66f709b | 1031 | return 1; |
e66f709b | 1032 | |
5f39d397 | 1033 | left = read_node_slot(root, parent, pslot - 1); |
e66f709b CM |
1034 | |
1035 | /* first, try to make some room in the middle buffer */ | |
5f39d397 | 1036 | if (left) { |
e66f709b | 1037 | u32 left_nr; |
925baedd CM |
1038 | |
1039 | btrfs_tree_lock(left); | |
5f39d397 | 1040 | left_nr = btrfs_header_nritems(left); |
33ade1f8 CM |
1041 | if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
1042 | wret = 1; | |
1043 | } else { | |
5f39d397 | 1044 | ret = btrfs_cow_block(trans, root, left, parent, |
65b51a00 | 1045 | pslot - 1, &left, 0); |
54aa1f4d CM |
1046 | if (ret) |
1047 | wret = 1; | |
1048 | else { | |
54aa1f4d | 1049 | wret = push_node_left(trans, root, |
971a1f66 | 1050 | left, mid, 0); |
54aa1f4d | 1051 | } |
33ade1f8 | 1052 | } |
e66f709b CM |
1053 | if (wret < 0) |
1054 | ret = wret; | |
1055 | if (wret == 0) { | |
5f39d397 | 1056 | struct btrfs_disk_key disk_key; |
e66f709b | 1057 | orig_slot += left_nr; |
5f39d397 CM |
1058 | btrfs_node_key(mid, &disk_key, 0); |
1059 | btrfs_set_node_key(parent, &disk_key, pslot); | |
1060 | btrfs_mark_buffer_dirty(parent); | |
1061 | if (btrfs_header_nritems(left) > orig_slot) { | |
1062 | path->nodes[level] = left; | |
e66f709b CM |
1063 | path->slots[level + 1] -= 1; |
1064 | path->slots[level] = orig_slot; | |
925baedd | 1065 | btrfs_tree_unlock(mid); |
5f39d397 | 1066 | free_extent_buffer(mid); |
e66f709b CM |
1067 | } else { |
1068 | orig_slot -= | |
5f39d397 | 1069 | btrfs_header_nritems(left); |
e66f709b | 1070 | path->slots[level] = orig_slot; |
925baedd | 1071 | btrfs_tree_unlock(left); |
5f39d397 | 1072 | free_extent_buffer(left); |
e66f709b | 1073 | } |
e66f709b CM |
1074 | return 0; |
1075 | } | |
925baedd | 1076 | btrfs_tree_unlock(left); |
5f39d397 | 1077 | free_extent_buffer(left); |
e66f709b | 1078 | } |
925baedd | 1079 | right = read_node_slot(root, parent, pslot + 1); |
e66f709b CM |
1080 | |
1081 | /* | |
1082 | * then try to empty the right most buffer into the middle | |
1083 | */ | |
5f39d397 | 1084 | if (right) { |
33ade1f8 | 1085 | u32 right_nr; |
925baedd | 1086 | btrfs_tree_lock(right); |
5f39d397 | 1087 | right_nr = btrfs_header_nritems(right); |
33ade1f8 CM |
1088 | if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
1089 | wret = 1; | |
1090 | } else { | |
5f39d397 CM |
1091 | ret = btrfs_cow_block(trans, root, right, |
1092 | parent, pslot + 1, | |
65b51a00 | 1093 | &right, 0); |
54aa1f4d CM |
1094 | if (ret) |
1095 | wret = 1; | |
1096 | else { | |
54aa1f4d | 1097 | wret = balance_node_right(trans, root, |
5f39d397 | 1098 | right, mid); |
54aa1f4d | 1099 | } |
33ade1f8 | 1100 | } |
e66f709b CM |
1101 | if (wret < 0) |
1102 | ret = wret; | |
1103 | if (wret == 0) { | |
5f39d397 CM |
1104 | struct btrfs_disk_key disk_key; |
1105 | ||
1106 | btrfs_node_key(right, &disk_key, 0); | |
1107 | btrfs_set_node_key(parent, &disk_key, pslot + 1); | |
1108 | btrfs_mark_buffer_dirty(parent); | |
1109 | ||
1110 | if (btrfs_header_nritems(mid) <= orig_slot) { | |
1111 | path->nodes[level] = right; | |
e66f709b CM |
1112 | path->slots[level + 1] += 1; |
1113 | path->slots[level] = orig_slot - | |
5f39d397 | 1114 | btrfs_header_nritems(mid); |
925baedd | 1115 | btrfs_tree_unlock(mid); |
5f39d397 | 1116 | free_extent_buffer(mid); |
e66f709b | 1117 | } else { |
925baedd | 1118 | btrfs_tree_unlock(right); |
5f39d397 | 1119 | free_extent_buffer(right); |
e66f709b | 1120 | } |
e66f709b CM |
1121 | return 0; |
1122 | } | |
925baedd | 1123 | btrfs_tree_unlock(right); |
5f39d397 | 1124 | free_extent_buffer(right); |
e66f709b | 1125 | } |
e66f709b CM |
1126 | return 1; |
1127 | } | |
1128 | ||
3c69faec CM |
1129 | /* |
1130 | * readahead one full node of leaves | |
1131 | */ | |
e02119d5 CM |
1132 | static noinline void reada_for_search(struct btrfs_root *root, |
1133 | struct btrfs_path *path, | |
1134 | int level, int slot, u64 objectid) | |
3c69faec | 1135 | { |
5f39d397 | 1136 | struct extent_buffer *node; |
01f46658 | 1137 | struct btrfs_disk_key disk_key; |
3c69faec | 1138 | u32 nritems; |
3c69faec | 1139 | u64 search; |
6b80053d CM |
1140 | u64 lowest_read; |
1141 | u64 highest_read; | |
1142 | u64 nread = 0; | |
3c69faec | 1143 | int direction = path->reada; |
5f39d397 | 1144 | struct extent_buffer *eb; |
6b80053d CM |
1145 | u32 nr; |
1146 | u32 blocksize; | |
1147 | u32 nscan = 0; | |
db94535d | 1148 | |
a6b6e75e | 1149 | if (level != 1) |
6702ed49 CM |
1150 | return; |
1151 | ||
1152 | if (!path->nodes[level]) | |
3c69faec CM |
1153 | return; |
1154 | ||
5f39d397 | 1155 | node = path->nodes[level]; |
925baedd | 1156 | |
3c69faec | 1157 | search = btrfs_node_blockptr(node, slot); |
6b80053d CM |
1158 | blocksize = btrfs_level_size(root, level - 1); |
1159 | eb = btrfs_find_tree_block(root, search, blocksize); | |
5f39d397 CM |
1160 | if (eb) { |
1161 | free_extent_buffer(eb); | |
3c69faec CM |
1162 | return; |
1163 | } | |
1164 | ||
6b80053d CM |
1165 | highest_read = search; |
1166 | lowest_read = search; | |
1167 | ||
5f39d397 | 1168 | nritems = btrfs_header_nritems(node); |
6b80053d | 1169 | nr = slot; |
3c69faec | 1170 | while(1) { |
6b80053d CM |
1171 | if (direction < 0) { |
1172 | if (nr == 0) | |
1173 | break; | |
1174 | nr--; | |
1175 | } else if (direction > 0) { | |
1176 | nr++; | |
1177 | if (nr >= nritems) | |
1178 | break; | |
3c69faec | 1179 | } |
01f46658 CM |
1180 | if (path->reada < 0 && objectid) { |
1181 | btrfs_node_key(node, &disk_key, nr); | |
1182 | if (btrfs_disk_key_objectid(&disk_key) != objectid) | |
1183 | break; | |
1184 | } | |
6b80053d CM |
1185 | search = btrfs_node_blockptr(node, nr); |
1186 | if ((search >= lowest_read && search <= highest_read) || | |
1187 | (search < lowest_read && lowest_read - search <= 32768) || | |
1188 | (search > highest_read && search - highest_read <= 32768)) { | |
ca7a79ad CM |
1189 | readahead_tree_block(root, search, blocksize, |
1190 | btrfs_node_ptr_generation(node, nr)); | |
6b80053d CM |
1191 | nread += blocksize; |
1192 | } | |
1193 | nscan++; | |
1194 | if (path->reada < 2 && (nread > (256 * 1024) || nscan > 32)) | |
1195 | break; | |
1196 | if(nread > (1024 * 1024) || nscan > 128) | |
1197 | break; | |
1198 | ||
1199 | if (search < lowest_read) | |
1200 | lowest_read = search; | |
1201 | if (search > highest_read) | |
1202 | highest_read = search; | |
3c69faec CM |
1203 | } |
1204 | } | |
925baedd | 1205 | |
e02119d5 CM |
1206 | static noinline void unlock_up(struct btrfs_path *path, int level, |
1207 | int lowest_unlock) | |
925baedd CM |
1208 | { |
1209 | int i; | |
1210 | int skip_level = level; | |
051e1b9f | 1211 | int no_skips = 0; |
925baedd CM |
1212 | struct extent_buffer *t; |
1213 | ||
1214 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { | |
1215 | if (!path->nodes[i]) | |
1216 | break; | |
1217 | if (!path->locks[i]) | |
1218 | break; | |
051e1b9f | 1219 | if (!no_skips && path->slots[i] == 0) { |
925baedd CM |
1220 | skip_level = i + 1; |
1221 | continue; | |
1222 | } | |
051e1b9f | 1223 | if (!no_skips && path->keep_locks) { |
925baedd CM |
1224 | u32 nritems; |
1225 | t = path->nodes[i]; | |
1226 | nritems = btrfs_header_nritems(t); | |
051e1b9f | 1227 | if (nritems < 1 || path->slots[i] >= nritems - 1) { |
925baedd CM |
1228 | skip_level = i + 1; |
1229 | continue; | |
1230 | } | |
1231 | } | |
051e1b9f CM |
1232 | if (skip_level < i && i >= lowest_unlock) |
1233 | no_skips = 1; | |
1234 | ||
925baedd CM |
1235 | t = path->nodes[i]; |
1236 | if (i >= lowest_unlock && i > skip_level && path->locks[i]) { | |
1237 | btrfs_tree_unlock(t); | |
1238 | path->locks[i] = 0; | |
1239 | } | |
1240 | } | |
1241 | } | |
1242 | ||
74123bd7 CM |
1243 | /* |
1244 | * look for key in the tree. path is filled in with nodes along the way | |
1245 | * if key is found, we return zero and you can find the item in the leaf | |
1246 | * level of the path (level 0) | |
1247 | * | |
1248 | * If the key isn't found, the path points to the slot where it should | |
aa5d6bed CM |
1249 | * be inserted, and 1 is returned. If there are other errors during the |
1250 | * search a negative error number is returned. | |
97571fd0 CM |
1251 | * |
1252 | * if ins_len > 0, nodes and leaves will be split as we walk down the | |
1253 | * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if | |
1254 | * possible) | |
74123bd7 | 1255 | */ |
e089f05c CM |
1256 | int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root |
1257 | *root, struct btrfs_key *key, struct btrfs_path *p, int | |
1258 | ins_len, int cow) | |
be0e5c09 | 1259 | { |
5f39d397 | 1260 | struct extent_buffer *b; |
051e1b9f | 1261 | struct extent_buffer *tmp; |
be0e5c09 CM |
1262 | int slot; |
1263 | int ret; | |
1264 | int level; | |
3c69faec | 1265 | int should_reada = p->reada; |
925baedd | 1266 | int lowest_unlock = 1; |
594a24eb | 1267 | int blocksize; |
9f3a7427 | 1268 | u8 lowest_level = 0; |
594a24eb CM |
1269 | u64 blocknr; |
1270 | u64 gen; | |
65b51a00 | 1271 | struct btrfs_key prealloc_block; |
9f3a7427 | 1272 | |
6702ed49 CM |
1273 | lowest_level = p->lowest_level; |
1274 | WARN_ON(lowest_level && ins_len); | |
22b0ebda | 1275 | WARN_ON(p->nodes[0] != NULL); |
333db94c | 1276 | WARN_ON(cow && root == root->fs_info->extent_root && |
925baedd | 1277 | !mutex_is_locked(&root->fs_info->alloc_mutex)); |
925baedd CM |
1278 | if (ins_len < 0) |
1279 | lowest_unlock = 2; | |
65b51a00 CM |
1280 | |
1281 | prealloc_block.objectid = 0; | |
1282 | ||
bb803951 | 1283 | again: |
5cd57b2c CM |
1284 | if (p->skip_locking) |
1285 | b = btrfs_root_node(root); | |
1286 | else | |
1287 | b = btrfs_lock_root_node(root); | |
925baedd | 1288 | |
eb60ceac | 1289 | while (b) { |
5f39d397 | 1290 | level = btrfs_header_level(b); |
65b51a00 CM |
1291 | |
1292 | /* | |
1293 | * setup the path here so we can release it under lock | |
1294 | * contention with the cow code | |
1295 | */ | |
1296 | p->nodes[level] = b; | |
1297 | if (!p->skip_locking) | |
1298 | p->locks[level] = 1; | |
1299 | ||
02217ed2 CM |
1300 | if (cow) { |
1301 | int wret; | |
65b51a00 CM |
1302 | |
1303 | /* is a cow on this block not required */ | |
1304 | spin_lock(&root->fs_info->hash_lock); | |
1305 | if (btrfs_header_generation(b) == trans->transid && | |
1306 | !btrfs_header_flag(b, BTRFS_HEADER_FLAG_WRITTEN)) { | |
1307 | spin_unlock(&root->fs_info->hash_lock); | |
1308 | goto cow_done; | |
1309 | } | |
1310 | spin_unlock(&root->fs_info->hash_lock); | |
1311 | ||
1312 | /* ok, we have to cow, is our old prealloc the right | |
1313 | * size? | |
1314 | */ | |
1315 | if (prealloc_block.objectid && | |
1316 | prealloc_block.offset != b->len) { | |
1317 | btrfs_free_reserved_extent(root, | |
1318 | prealloc_block.objectid, | |
1319 | prealloc_block.offset); | |
1320 | prealloc_block.objectid = 0; | |
1321 | } | |
1322 | ||
1323 | /* | |
1324 | * for higher level blocks, try not to allocate blocks | |
1325 | * with the block and the parent locks held. | |
1326 | */ | |
1327 | if (level > 1 && !prealloc_block.objectid && | |
1328 | btrfs_path_lock_waiting(p, level)) { | |
1329 | u32 size = b->len; | |
1330 | u64 hint = b->start; | |
1331 | ||
1332 | btrfs_release_path(root, p); | |
1333 | ret = btrfs_reserve_extent(trans, root, | |
1334 | size, size, 0, | |
1335 | hint, (u64)-1, | |
1336 | &prealloc_block, 0); | |
1337 | BUG_ON(ret); | |
1338 | goto again; | |
1339 | } | |
1340 | ||
e20d96d6 CM |
1341 | wret = btrfs_cow_block(trans, root, b, |
1342 | p->nodes[level + 1], | |
1343 | p->slots[level + 1], | |
65b51a00 CM |
1344 | &b, prealloc_block.objectid); |
1345 | prealloc_block.objectid = 0; | |
54aa1f4d | 1346 | if (wret) { |
5f39d397 | 1347 | free_extent_buffer(b); |
65b51a00 CM |
1348 | ret = wret; |
1349 | goto done; | |
54aa1f4d | 1350 | } |
02217ed2 | 1351 | } |
65b51a00 | 1352 | cow_done: |
02217ed2 | 1353 | BUG_ON(!cow && ins_len); |
5f39d397 | 1354 | if (level != btrfs_header_level(b)) |
2c90e5d6 | 1355 | WARN_ON(1); |
5f39d397 | 1356 | level = btrfs_header_level(b); |
65b51a00 | 1357 | |
eb60ceac | 1358 | p->nodes[level] = b; |
5cd57b2c CM |
1359 | if (!p->skip_locking) |
1360 | p->locks[level] = 1; | |
65b51a00 | 1361 | |
123abc88 | 1362 | ret = check_block(root, p, level); |
65b51a00 CM |
1363 | if (ret) { |
1364 | ret = -1; | |
1365 | goto done; | |
1366 | } | |
925baedd | 1367 | |
5f39d397 CM |
1368 | ret = bin_search(b, key, level, &slot); |
1369 | if (level != 0) { | |
be0e5c09 CM |
1370 | if (ret && slot > 0) |
1371 | slot -= 1; | |
1372 | p->slots[level] = slot; | |
5f39d397 | 1373 | if (ins_len > 0 && btrfs_header_nritems(b) >= |
1514794e | 1374 | BTRFS_NODEPTRS_PER_BLOCK(root) - 3) { |
e089f05c | 1375 | int sret = split_node(trans, root, p, level); |
5c680ed6 | 1376 | BUG_ON(sret > 0); |
65b51a00 CM |
1377 | if (sret) { |
1378 | ret = sret; | |
1379 | goto done; | |
1380 | } | |
5c680ed6 | 1381 | b = p->nodes[level]; |
5c680ed6 | 1382 | slot = p->slots[level]; |
bb803951 | 1383 | } else if (ins_len < 0) { |
e089f05c CM |
1384 | int sret = balance_level(trans, root, p, |
1385 | level); | |
65b51a00 CM |
1386 | if (sret) { |
1387 | ret = sret; | |
1388 | goto done; | |
1389 | } | |
bb803951 | 1390 | b = p->nodes[level]; |
f510cfec CM |
1391 | if (!b) { |
1392 | btrfs_release_path(NULL, p); | |
bb803951 | 1393 | goto again; |
f510cfec | 1394 | } |
bb803951 | 1395 | slot = p->slots[level]; |
5f39d397 | 1396 | BUG_ON(btrfs_header_nritems(b) == 1); |
5c680ed6 | 1397 | } |
f9efa9c7 CM |
1398 | unlock_up(p, level, lowest_unlock); |
1399 | ||
9f3a7427 | 1400 | /* this is only true while dropping a snapshot */ |
925baedd | 1401 | if (level == lowest_level) { |
9f3a7427 | 1402 | break; |
925baedd | 1403 | } |
ca7a79ad | 1404 | |
594a24eb CM |
1405 | blocknr = btrfs_node_blockptr(b, slot); |
1406 | gen = btrfs_node_ptr_generation(b, slot); | |
1407 | blocksize = btrfs_level_size(root, level - 1); | |
1408 | ||
1409 | tmp = btrfs_find_tree_block(root, blocknr, blocksize); | |
1410 | if (tmp && btrfs_buffer_uptodate(tmp, gen)) { | |
051e1b9f CM |
1411 | b = tmp; |
1412 | } else { | |
1413 | /* | |
1414 | * reduce lock contention at high levels | |
1415 | * of the btree by dropping locks before | |
1416 | * we read. | |
1417 | */ | |
1418 | if (level > 1) { | |
1419 | btrfs_release_path(NULL, p); | |
594a24eb CM |
1420 | if (tmp) |
1421 | free_extent_buffer(tmp); | |
f9efa9c7 CM |
1422 | if (should_reada) |
1423 | reada_for_search(root, p, | |
1424 | level, slot, | |
1425 | key->objectid); | |
1426 | ||
594a24eb CM |
1427 | tmp = read_tree_block(root, blocknr, |
1428 | blocksize, gen); | |
051e1b9f CM |
1429 | if (tmp) |
1430 | free_extent_buffer(tmp); | |
1431 | goto again; | |
1432 | } else { | |
a74a4b97 CM |
1433 | if (tmp) |
1434 | free_extent_buffer(tmp); | |
f9efa9c7 CM |
1435 | if (should_reada) |
1436 | reada_for_search(root, p, | |
1437 | level, slot, | |
1438 | key->objectid); | |
051e1b9f CM |
1439 | b = read_node_slot(root, b, slot); |
1440 | } | |
1441 | } | |
5cd57b2c CM |
1442 | if (!p->skip_locking) |
1443 | btrfs_tree_lock(b); | |
be0e5c09 CM |
1444 | } else { |
1445 | p->slots[level] = slot; | |
5f39d397 | 1446 | if (ins_len > 0 && btrfs_leaf_free_space(root, b) < |
0783fcfc | 1447 | sizeof(struct btrfs_item) + ins_len) { |
d4dbff95 | 1448 | int sret = split_leaf(trans, root, key, |
cc0c5538 | 1449 | p, ins_len, ret == 0); |
5c680ed6 | 1450 | BUG_ON(sret > 0); |
65b51a00 CM |
1451 | if (sret) { |
1452 | ret = sret; | |
1453 | goto done; | |
1454 | } | |
5c680ed6 | 1455 | } |
925baedd | 1456 | unlock_up(p, level, lowest_unlock); |
65b51a00 | 1457 | goto done; |
be0e5c09 CM |
1458 | } |
1459 | } | |
65b51a00 CM |
1460 | ret = 1; |
1461 | done: | |
1462 | if (prealloc_block.objectid) { | |
1463 | btrfs_free_reserved_extent(root, | |
1464 | prealloc_block.objectid, | |
1465 | prealloc_block.offset); | |
1466 | } | |
1467 | ||
1468 | return ret; | |
be0e5c09 CM |
1469 | } |
1470 | ||
74123bd7 CM |
1471 | /* |
1472 | * adjust the pointers going up the tree, starting at level | |
1473 | * making sure the right key of each node is points to 'key'. | |
1474 | * This is used after shifting pointers to the left, so it stops | |
1475 | * fixing up pointers when a given leaf/node is not in slot 0 of the | |
1476 | * higher levels | |
aa5d6bed CM |
1477 | * |
1478 | * If this fails to write a tree block, it returns -1, but continues | |
1479 | * fixing up the blocks in ram so the tree is consistent. | |
74123bd7 | 1480 | */ |
5f39d397 CM |
1481 | static int fixup_low_keys(struct btrfs_trans_handle *trans, |
1482 | struct btrfs_root *root, struct btrfs_path *path, | |
1483 | struct btrfs_disk_key *key, int level) | |
be0e5c09 CM |
1484 | { |
1485 | int i; | |
aa5d6bed | 1486 | int ret = 0; |
5f39d397 CM |
1487 | struct extent_buffer *t; |
1488 | ||
234b63a0 | 1489 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
be0e5c09 | 1490 | int tslot = path->slots[i]; |
eb60ceac | 1491 | if (!path->nodes[i]) |
be0e5c09 | 1492 | break; |
5f39d397 CM |
1493 | t = path->nodes[i]; |
1494 | btrfs_set_node_key(t, key, tslot); | |
d6025579 | 1495 | btrfs_mark_buffer_dirty(path->nodes[i]); |
be0e5c09 CM |
1496 | if (tslot != 0) |
1497 | break; | |
1498 | } | |
aa5d6bed | 1499 | return ret; |
be0e5c09 CM |
1500 | } |
1501 | ||
74123bd7 CM |
1502 | /* |
1503 | * try to push data from one node into the next node left in the | |
79f95c82 | 1504 | * tree. |
aa5d6bed CM |
1505 | * |
1506 | * returns 0 if some ptrs were pushed left, < 0 if there was some horrible | |
1507 | * error, and > 0 if there was no room in the left hand block. | |
74123bd7 | 1508 | */ |
98ed5174 CM |
1509 | static int push_node_left(struct btrfs_trans_handle *trans, |
1510 | struct btrfs_root *root, struct extent_buffer *dst, | |
971a1f66 | 1511 | struct extent_buffer *src, int empty) |
be0e5c09 | 1512 | { |
be0e5c09 | 1513 | int push_items = 0; |
bb803951 CM |
1514 | int src_nritems; |
1515 | int dst_nritems; | |
aa5d6bed | 1516 | int ret = 0; |
be0e5c09 | 1517 | |
5f39d397 CM |
1518 | src_nritems = btrfs_header_nritems(src); |
1519 | dst_nritems = btrfs_header_nritems(dst); | |
123abc88 | 1520 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
7bb86316 CM |
1521 | WARN_ON(btrfs_header_generation(src) != trans->transid); |
1522 | WARN_ON(btrfs_header_generation(dst) != trans->transid); | |
54aa1f4d | 1523 | |
bce4eae9 | 1524 | if (!empty && src_nritems <= 8) |
971a1f66 CM |
1525 | return 1; |
1526 | ||
eb60ceac | 1527 | if (push_items <= 0) { |
be0e5c09 | 1528 | return 1; |
eb60ceac | 1529 | } |
be0e5c09 | 1530 | |
bce4eae9 | 1531 | if (empty) { |
971a1f66 | 1532 | push_items = min(src_nritems, push_items); |
bce4eae9 CM |
1533 | if (push_items < src_nritems) { |
1534 | /* leave at least 8 pointers in the node if | |
1535 | * we aren't going to empty it | |
1536 | */ | |
1537 | if (src_nritems - push_items < 8) { | |
1538 | if (push_items <= 8) | |
1539 | return 1; | |
1540 | push_items -= 8; | |
1541 | } | |
1542 | } | |
1543 | } else | |
1544 | push_items = min(src_nritems - 8, push_items); | |
79f95c82 | 1545 | |
5f39d397 CM |
1546 | copy_extent_buffer(dst, src, |
1547 | btrfs_node_key_ptr_offset(dst_nritems), | |
1548 | btrfs_node_key_ptr_offset(0), | |
1549 | push_items * sizeof(struct btrfs_key_ptr)); | |
1550 | ||
bb803951 | 1551 | if (push_items < src_nritems) { |
5f39d397 CM |
1552 | memmove_extent_buffer(src, btrfs_node_key_ptr_offset(0), |
1553 | btrfs_node_key_ptr_offset(push_items), | |
1554 | (src_nritems - push_items) * | |
1555 | sizeof(struct btrfs_key_ptr)); | |
1556 | } | |
1557 | btrfs_set_header_nritems(src, src_nritems - push_items); | |
1558 | btrfs_set_header_nritems(dst, dst_nritems + push_items); | |
1559 | btrfs_mark_buffer_dirty(src); | |
1560 | btrfs_mark_buffer_dirty(dst); | |
79f95c82 CM |
1561 | return ret; |
1562 | } | |
1563 | ||
1564 | /* | |
1565 | * try to push data from one node into the next node right in the | |
1566 | * tree. | |
1567 | * | |
1568 | * returns 0 if some ptrs were pushed, < 0 if there was some horrible | |
1569 | * error, and > 0 if there was no room in the right hand block. | |
1570 | * | |
1571 | * this will only push up to 1/2 the contents of the left node over | |
1572 | */ | |
5f39d397 CM |
1573 | static int balance_node_right(struct btrfs_trans_handle *trans, |
1574 | struct btrfs_root *root, | |
1575 | struct extent_buffer *dst, | |
1576 | struct extent_buffer *src) | |
79f95c82 | 1577 | { |
79f95c82 CM |
1578 | int push_items = 0; |
1579 | int max_push; | |
1580 | int src_nritems; | |
1581 | int dst_nritems; | |
1582 | int ret = 0; | |
79f95c82 | 1583 | |
7bb86316 CM |
1584 | WARN_ON(btrfs_header_generation(src) != trans->transid); |
1585 | WARN_ON(btrfs_header_generation(dst) != trans->transid); | |
1586 | ||
5f39d397 CM |
1587 | src_nritems = btrfs_header_nritems(src); |
1588 | dst_nritems = btrfs_header_nritems(dst); | |
123abc88 | 1589 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
bce4eae9 | 1590 | if (push_items <= 0) { |
79f95c82 | 1591 | return 1; |
bce4eae9 CM |
1592 | } |
1593 | ||
1594 | if (src_nritems < 4) { | |
1595 | return 1; | |
1596 | } | |
79f95c82 CM |
1597 | |
1598 | max_push = src_nritems / 2 + 1; | |
1599 | /* don't try to empty the node */ | |
bce4eae9 | 1600 | if (max_push >= src_nritems) { |
79f95c82 | 1601 | return 1; |
bce4eae9 | 1602 | } |
252c38f0 | 1603 | |
79f95c82 CM |
1604 | if (max_push < push_items) |
1605 | push_items = max_push; | |
1606 | ||
5f39d397 CM |
1607 | memmove_extent_buffer(dst, btrfs_node_key_ptr_offset(push_items), |
1608 | btrfs_node_key_ptr_offset(0), | |
1609 | (dst_nritems) * | |
1610 | sizeof(struct btrfs_key_ptr)); | |
d6025579 | 1611 | |
5f39d397 CM |
1612 | copy_extent_buffer(dst, src, |
1613 | btrfs_node_key_ptr_offset(0), | |
1614 | btrfs_node_key_ptr_offset(src_nritems - push_items), | |
1615 | push_items * sizeof(struct btrfs_key_ptr)); | |
79f95c82 | 1616 | |
5f39d397 CM |
1617 | btrfs_set_header_nritems(src, src_nritems - push_items); |
1618 | btrfs_set_header_nritems(dst, dst_nritems + push_items); | |
79f95c82 | 1619 | |
5f39d397 CM |
1620 | btrfs_mark_buffer_dirty(src); |
1621 | btrfs_mark_buffer_dirty(dst); | |
aa5d6bed | 1622 | return ret; |
be0e5c09 CM |
1623 | } |
1624 | ||
97571fd0 CM |
1625 | /* |
1626 | * helper function to insert a new root level in the tree. | |
1627 | * A new node is allocated, and a single item is inserted to | |
1628 | * point to the existing root | |
aa5d6bed CM |
1629 | * |
1630 | * returns zero on success or < 0 on failure. | |
97571fd0 | 1631 | */ |
98ed5174 | 1632 | static int noinline insert_new_root(struct btrfs_trans_handle *trans, |
5f39d397 CM |
1633 | struct btrfs_root *root, |
1634 | struct btrfs_path *path, int level) | |
5c680ed6 | 1635 | { |
7bb86316 CM |
1636 | u64 root_gen; |
1637 | u64 lower_gen; | |
5f39d397 CM |
1638 | struct extent_buffer *lower; |
1639 | struct extent_buffer *c; | |
925baedd | 1640 | struct extent_buffer *old; |
5f39d397 | 1641 | struct btrfs_disk_key lower_key; |
5c680ed6 CM |
1642 | |
1643 | BUG_ON(path->nodes[level]); | |
1644 | BUG_ON(path->nodes[level-1] != root->node); | |
1645 | ||
7bb86316 CM |
1646 | if (root->ref_cows) |
1647 | root_gen = trans->transid; | |
1648 | else | |
1649 | root_gen = 0; | |
1650 | ||
1651 | lower = path->nodes[level-1]; | |
1652 | if (level == 1) | |
1653 | btrfs_item_key(lower, &lower_key, 0); | |
1654 | else | |
1655 | btrfs_node_key(lower, &lower_key, 0); | |
1656 | ||
925baedd | 1657 | c = btrfs_alloc_free_block(trans, root, root->nodesize, |
7bb86316 CM |
1658 | root->root_key.objectid, |
1659 | root_gen, lower_key.objectid, level, | |
db94535d | 1660 | root->node->start, 0); |
5f39d397 CM |
1661 | if (IS_ERR(c)) |
1662 | return PTR_ERR(c); | |
925baedd | 1663 | |
5f39d397 CM |
1664 | memset_extent_buffer(c, 0, 0, root->nodesize); |
1665 | btrfs_set_header_nritems(c, 1); | |
1666 | btrfs_set_header_level(c, level); | |
db94535d | 1667 | btrfs_set_header_bytenr(c, c->start); |
5f39d397 CM |
1668 | btrfs_set_header_generation(c, trans->transid); |
1669 | btrfs_set_header_owner(c, root->root_key.objectid); | |
5f39d397 CM |
1670 | |
1671 | write_extent_buffer(c, root->fs_info->fsid, | |
1672 | (unsigned long)btrfs_header_fsid(c), | |
1673 | BTRFS_FSID_SIZE); | |
e17cade2 CM |
1674 | |
1675 | write_extent_buffer(c, root->fs_info->chunk_tree_uuid, | |
1676 | (unsigned long)btrfs_header_chunk_tree_uuid(c), | |
1677 | BTRFS_UUID_SIZE); | |
1678 | ||
5f39d397 | 1679 | btrfs_set_node_key(c, &lower_key, 0); |
db94535d | 1680 | btrfs_set_node_blockptr(c, 0, lower->start); |
7bb86316 CM |
1681 | lower_gen = btrfs_header_generation(lower); |
1682 | WARN_ON(lower_gen == 0); | |
1683 | ||
1684 | btrfs_set_node_ptr_generation(c, 0, lower_gen); | |
d5719762 | 1685 | |
5f39d397 | 1686 | btrfs_mark_buffer_dirty(c); |
d5719762 | 1687 | |
925baedd CM |
1688 | spin_lock(&root->node_lock); |
1689 | old = root->node; | |
5f39d397 | 1690 | root->node = c; |
925baedd CM |
1691 | spin_unlock(&root->node_lock); |
1692 | ||
1693 | /* the super has an extra ref to root->node */ | |
1694 | free_extent_buffer(old); | |
1695 | ||
0b86a832 | 1696 | add_root_to_dirty_list(root); |
5f39d397 CM |
1697 | extent_buffer_get(c); |
1698 | path->nodes[level] = c; | |
925baedd | 1699 | path->locks[level] = 1; |
5c680ed6 | 1700 | path->slots[level] = 0; |
7bb86316 CM |
1701 | |
1702 | if (root->ref_cows && lower_gen != trans->transid) { | |
1703 | struct btrfs_path *back_path = btrfs_alloc_path(); | |
1704 | int ret; | |
925baedd | 1705 | mutex_lock(&root->fs_info->alloc_mutex); |
7bb86316 CM |
1706 | ret = btrfs_insert_extent_backref(trans, |
1707 | root->fs_info->extent_root, | |
1708 | path, lower->start, | |
1709 | root->root_key.objectid, | |
1710 | trans->transid, 0, 0); | |
1711 | BUG_ON(ret); | |
925baedd | 1712 | mutex_unlock(&root->fs_info->alloc_mutex); |
7bb86316 CM |
1713 | btrfs_free_path(back_path); |
1714 | } | |
5c680ed6 CM |
1715 | return 0; |
1716 | } | |
1717 | ||
74123bd7 CM |
1718 | /* |
1719 | * worker function to insert a single pointer in a node. | |
1720 | * the node should have enough room for the pointer already | |
97571fd0 | 1721 | * |
74123bd7 CM |
1722 | * slot and level indicate where you want the key to go, and |
1723 | * blocknr is the block the key points to. | |
aa5d6bed CM |
1724 | * |
1725 | * returns zero on success and < 0 on any error | |
74123bd7 | 1726 | */ |
e089f05c CM |
1727 | static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root |
1728 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
db94535d | 1729 | *key, u64 bytenr, int slot, int level) |
74123bd7 | 1730 | { |
5f39d397 | 1731 | struct extent_buffer *lower; |
74123bd7 | 1732 | int nritems; |
5c680ed6 CM |
1733 | |
1734 | BUG_ON(!path->nodes[level]); | |
5f39d397 CM |
1735 | lower = path->nodes[level]; |
1736 | nritems = btrfs_header_nritems(lower); | |
74123bd7 CM |
1737 | if (slot > nritems) |
1738 | BUG(); | |
123abc88 | 1739 | if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root)) |
74123bd7 CM |
1740 | BUG(); |
1741 | if (slot != nritems) { | |
5f39d397 CM |
1742 | memmove_extent_buffer(lower, |
1743 | btrfs_node_key_ptr_offset(slot + 1), | |
1744 | btrfs_node_key_ptr_offset(slot), | |
d6025579 | 1745 | (nritems - slot) * sizeof(struct btrfs_key_ptr)); |
74123bd7 | 1746 | } |
5f39d397 | 1747 | btrfs_set_node_key(lower, key, slot); |
db94535d | 1748 | btrfs_set_node_blockptr(lower, slot, bytenr); |
74493f7a CM |
1749 | WARN_ON(trans->transid == 0); |
1750 | btrfs_set_node_ptr_generation(lower, slot, trans->transid); | |
5f39d397 CM |
1751 | btrfs_set_header_nritems(lower, nritems + 1); |
1752 | btrfs_mark_buffer_dirty(lower); | |
74123bd7 CM |
1753 | return 0; |
1754 | } | |
1755 | ||
97571fd0 CM |
1756 | /* |
1757 | * split the node at the specified level in path in two. | |
1758 | * The path is corrected to point to the appropriate node after the split | |
1759 | * | |
1760 | * Before splitting this tries to make some room in the node by pushing | |
1761 | * left and right, if either one works, it returns right away. | |
aa5d6bed CM |
1762 | * |
1763 | * returns 0 on success and < 0 on failure | |
97571fd0 | 1764 | */ |
e02119d5 CM |
1765 | static noinline int split_node(struct btrfs_trans_handle *trans, |
1766 | struct btrfs_root *root, | |
1767 | struct btrfs_path *path, int level) | |
be0e5c09 | 1768 | { |
7bb86316 | 1769 | u64 root_gen; |
5f39d397 CM |
1770 | struct extent_buffer *c; |
1771 | struct extent_buffer *split; | |
1772 | struct btrfs_disk_key disk_key; | |
be0e5c09 | 1773 | int mid; |
5c680ed6 | 1774 | int ret; |
aa5d6bed | 1775 | int wret; |
7518a238 | 1776 | u32 c_nritems; |
eb60ceac | 1777 | |
5f39d397 | 1778 | c = path->nodes[level]; |
7bb86316 | 1779 | WARN_ON(btrfs_header_generation(c) != trans->transid); |
5f39d397 | 1780 | if (c == root->node) { |
5c680ed6 | 1781 | /* trying to split the root, lets make a new one */ |
e089f05c | 1782 | ret = insert_new_root(trans, root, path, level + 1); |
5c680ed6 CM |
1783 | if (ret) |
1784 | return ret; | |
e66f709b CM |
1785 | } else { |
1786 | ret = push_nodes_for_insert(trans, root, path, level); | |
5f39d397 CM |
1787 | c = path->nodes[level]; |
1788 | if (!ret && btrfs_header_nritems(c) < | |
c448acf0 | 1789 | BTRFS_NODEPTRS_PER_BLOCK(root) - 3) |
e66f709b | 1790 | return 0; |
54aa1f4d CM |
1791 | if (ret < 0) |
1792 | return ret; | |
be0e5c09 | 1793 | } |
e66f709b | 1794 | |
5f39d397 | 1795 | c_nritems = btrfs_header_nritems(c); |
7bb86316 CM |
1796 | if (root->ref_cows) |
1797 | root_gen = trans->transid; | |
1798 | else | |
1799 | root_gen = 0; | |
1800 | ||
1801 | btrfs_node_key(c, &disk_key, 0); | |
925baedd | 1802 | split = btrfs_alloc_free_block(trans, root, root->nodesize, |
7bb86316 CM |
1803 | root->root_key.objectid, |
1804 | root_gen, | |
1805 | btrfs_disk_key_objectid(&disk_key), | |
1806 | level, c->start, 0); | |
5f39d397 CM |
1807 | if (IS_ERR(split)) |
1808 | return PTR_ERR(split); | |
1809 | ||
1810 | btrfs_set_header_flags(split, btrfs_header_flags(c)); | |
1811 | btrfs_set_header_level(split, btrfs_header_level(c)); | |
db94535d | 1812 | btrfs_set_header_bytenr(split, split->start); |
5f39d397 CM |
1813 | btrfs_set_header_generation(split, trans->transid); |
1814 | btrfs_set_header_owner(split, root->root_key.objectid); | |
63b10fc4 | 1815 | btrfs_set_header_flags(split, 0); |
5f39d397 CM |
1816 | write_extent_buffer(split, root->fs_info->fsid, |
1817 | (unsigned long)btrfs_header_fsid(split), | |
1818 | BTRFS_FSID_SIZE); | |
e17cade2 CM |
1819 | write_extent_buffer(split, root->fs_info->chunk_tree_uuid, |
1820 | (unsigned long)btrfs_header_chunk_tree_uuid(split), | |
1821 | BTRFS_UUID_SIZE); | |
54aa1f4d | 1822 | |
7518a238 | 1823 | mid = (c_nritems + 1) / 2; |
5f39d397 CM |
1824 | |
1825 | copy_extent_buffer(split, c, | |
1826 | btrfs_node_key_ptr_offset(0), | |
1827 | btrfs_node_key_ptr_offset(mid), | |
1828 | (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); | |
1829 | btrfs_set_header_nritems(split, c_nritems - mid); | |
1830 | btrfs_set_header_nritems(c, mid); | |
aa5d6bed CM |
1831 | ret = 0; |
1832 | ||
5f39d397 CM |
1833 | btrfs_mark_buffer_dirty(c); |
1834 | btrfs_mark_buffer_dirty(split); | |
1835 | ||
1836 | btrfs_node_key(split, &disk_key, 0); | |
db94535d | 1837 | wret = insert_ptr(trans, root, path, &disk_key, split->start, |
5f39d397 | 1838 | path->slots[level + 1] + 1, |
123abc88 | 1839 | level + 1); |
aa5d6bed CM |
1840 | if (wret) |
1841 | ret = wret; | |
1842 | ||
5de08d7d | 1843 | if (path->slots[level] >= mid) { |
5c680ed6 | 1844 | path->slots[level] -= mid; |
925baedd | 1845 | btrfs_tree_unlock(c); |
5f39d397 CM |
1846 | free_extent_buffer(c); |
1847 | path->nodes[level] = split; | |
5c680ed6 CM |
1848 | path->slots[level + 1] += 1; |
1849 | } else { | |
925baedd | 1850 | btrfs_tree_unlock(split); |
5f39d397 | 1851 | free_extent_buffer(split); |
be0e5c09 | 1852 | } |
aa5d6bed | 1853 | return ret; |
be0e5c09 CM |
1854 | } |
1855 | ||
74123bd7 CM |
1856 | /* |
1857 | * how many bytes are required to store the items in a leaf. start | |
1858 | * and nr indicate which items in the leaf to check. This totals up the | |
1859 | * space used both by the item structs and the item data | |
1860 | */ | |
5f39d397 | 1861 | static int leaf_space_used(struct extent_buffer *l, int start, int nr) |
be0e5c09 CM |
1862 | { |
1863 | int data_len; | |
5f39d397 | 1864 | int nritems = btrfs_header_nritems(l); |
d4dbff95 | 1865 | int end = min(nritems, start + nr) - 1; |
be0e5c09 CM |
1866 | |
1867 | if (!nr) | |
1868 | return 0; | |
5f39d397 CM |
1869 | data_len = btrfs_item_end_nr(l, start); |
1870 | data_len = data_len - btrfs_item_offset_nr(l, end); | |
0783fcfc | 1871 | data_len += sizeof(struct btrfs_item) * nr; |
d4dbff95 | 1872 | WARN_ON(data_len < 0); |
be0e5c09 CM |
1873 | return data_len; |
1874 | } | |
1875 | ||
d4dbff95 CM |
1876 | /* |
1877 | * The space between the end of the leaf items and | |
1878 | * the start of the leaf data. IOW, how much room | |
1879 | * the leaf has left for both items and data | |
1880 | */ | |
e02119d5 CM |
1881 | int noinline btrfs_leaf_free_space(struct btrfs_root *root, |
1882 | struct extent_buffer *leaf) | |
d4dbff95 | 1883 | { |
5f39d397 CM |
1884 | int nritems = btrfs_header_nritems(leaf); |
1885 | int ret; | |
1886 | ret = BTRFS_LEAF_DATA_SIZE(root) - leaf_space_used(leaf, 0, nritems); | |
1887 | if (ret < 0) { | |
1888 | printk("leaf free space ret %d, leaf data size %lu, used %d nritems %d\n", | |
ae2f5411 | 1889 | ret, (unsigned long) BTRFS_LEAF_DATA_SIZE(root), |
5f39d397 CM |
1890 | leaf_space_used(leaf, 0, nritems), nritems); |
1891 | } | |
1892 | return ret; | |
d4dbff95 CM |
1893 | } |
1894 | ||
00ec4c51 CM |
1895 | /* |
1896 | * push some data in the path leaf to the right, trying to free up at | |
1897 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
aa5d6bed CM |
1898 | * |
1899 | * returns 1 if the push failed because the other node didn't have enough | |
1900 | * room, 0 if everything worked out and < 0 if there were major errors. | |
00ec4c51 | 1901 | */ |
e089f05c | 1902 | static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root |
34a38218 CM |
1903 | *root, struct btrfs_path *path, int data_size, |
1904 | int empty) | |
00ec4c51 | 1905 | { |
5f39d397 CM |
1906 | struct extent_buffer *left = path->nodes[0]; |
1907 | struct extent_buffer *right; | |
1908 | struct extent_buffer *upper; | |
1909 | struct btrfs_disk_key disk_key; | |
00ec4c51 | 1910 | int slot; |
34a38218 | 1911 | u32 i; |
00ec4c51 CM |
1912 | int free_space; |
1913 | int push_space = 0; | |
1914 | int push_items = 0; | |
0783fcfc | 1915 | struct btrfs_item *item; |
7518a238 | 1916 | u32 left_nritems; |
34a38218 | 1917 | u32 nr; |
7518a238 | 1918 | u32 right_nritems; |
5f39d397 | 1919 | u32 data_end; |
db94535d | 1920 | u32 this_item_size; |
54aa1f4d | 1921 | int ret; |
00ec4c51 CM |
1922 | |
1923 | slot = path->slots[1]; | |
1924 | if (!path->nodes[1]) { | |
1925 | return 1; | |
1926 | } | |
1927 | upper = path->nodes[1]; | |
5f39d397 | 1928 | if (slot >= btrfs_header_nritems(upper) - 1) |
00ec4c51 | 1929 | return 1; |
5f39d397 | 1930 | |
a2135011 CM |
1931 | WARN_ON(!btrfs_tree_locked(path->nodes[1])); |
1932 | ||
ca7a79ad | 1933 | right = read_node_slot(root, upper, slot + 1); |
925baedd | 1934 | btrfs_tree_lock(right); |
123abc88 | 1935 | free_space = btrfs_leaf_free_space(root, right); |
925baedd CM |
1936 | if (free_space < data_size + sizeof(struct btrfs_item)) |
1937 | goto out_unlock; | |
5f39d397 | 1938 | |
02217ed2 | 1939 | /* cow and double check */ |
5f39d397 | 1940 | ret = btrfs_cow_block(trans, root, right, upper, |
65b51a00 | 1941 | slot + 1, &right, 0); |
925baedd CM |
1942 | if (ret) |
1943 | goto out_unlock; | |
1944 | ||
123abc88 | 1945 | free_space = btrfs_leaf_free_space(root, right); |
925baedd CM |
1946 | if (free_space < data_size + sizeof(struct btrfs_item)) |
1947 | goto out_unlock; | |
02217ed2 | 1948 | |
5f39d397 | 1949 | left_nritems = btrfs_header_nritems(left); |
925baedd CM |
1950 | if (left_nritems == 0) |
1951 | goto out_unlock; | |
5f39d397 | 1952 | |
34a38218 CM |
1953 | if (empty) |
1954 | nr = 0; | |
1955 | else | |
1956 | nr = 1; | |
1957 | ||
1958 | i = left_nritems - 1; | |
1959 | while (i >= nr) { | |
5f39d397 | 1960 | item = btrfs_item_nr(left, i); |
db94535d | 1961 | |
00ec4c51 CM |
1962 | if (path->slots[0] == i) |
1963 | push_space += data_size + sizeof(*item); | |
db94535d CM |
1964 | |
1965 | if (!left->map_token) { | |
1966 | map_extent_buffer(left, (unsigned long)item, | |
1967 | sizeof(struct btrfs_item), | |
1968 | &left->map_token, &left->kaddr, | |
1969 | &left->map_start, &left->map_len, | |
1970 | KM_USER1); | |
1971 | } | |
1972 | ||
1973 | this_item_size = btrfs_item_size(left, item); | |
1974 | if (this_item_size + sizeof(*item) + push_space > free_space) | |
00ec4c51 CM |
1975 | break; |
1976 | push_items++; | |
db94535d | 1977 | push_space += this_item_size + sizeof(*item); |
34a38218 CM |
1978 | if (i == 0) |
1979 | break; | |
1980 | i--; | |
db94535d CM |
1981 | } |
1982 | if (left->map_token) { | |
1983 | unmap_extent_buffer(left, left->map_token, KM_USER1); | |
1984 | left->map_token = NULL; | |
00ec4c51 | 1985 | } |
5f39d397 | 1986 | |
925baedd CM |
1987 | if (push_items == 0) |
1988 | goto out_unlock; | |
5f39d397 | 1989 | |
34a38218 | 1990 | if (!empty && push_items == left_nritems) |
a429e513 | 1991 | WARN_ON(1); |
5f39d397 | 1992 | |
00ec4c51 | 1993 | /* push left to right */ |
5f39d397 | 1994 | right_nritems = btrfs_header_nritems(right); |
34a38218 | 1995 | |
5f39d397 | 1996 | push_space = btrfs_item_end_nr(left, left_nritems - push_items); |
123abc88 | 1997 | push_space -= leaf_data_end(root, left); |
5f39d397 | 1998 | |
00ec4c51 | 1999 | /* make room in the right data area */ |
5f39d397 CM |
2000 | data_end = leaf_data_end(root, right); |
2001 | memmove_extent_buffer(right, | |
2002 | btrfs_leaf_data(right) + data_end - push_space, | |
2003 | btrfs_leaf_data(right) + data_end, | |
2004 | BTRFS_LEAF_DATA_SIZE(root) - data_end); | |
2005 | ||
00ec4c51 | 2006 | /* copy from the left data area */ |
5f39d397 | 2007 | copy_extent_buffer(right, left, btrfs_leaf_data(right) + |
d6025579 CM |
2008 | BTRFS_LEAF_DATA_SIZE(root) - push_space, |
2009 | btrfs_leaf_data(left) + leaf_data_end(root, left), | |
2010 | push_space); | |
5f39d397 CM |
2011 | |
2012 | memmove_extent_buffer(right, btrfs_item_nr_offset(push_items), | |
2013 | btrfs_item_nr_offset(0), | |
2014 | right_nritems * sizeof(struct btrfs_item)); | |
2015 | ||
00ec4c51 | 2016 | /* copy the items from left to right */ |
5f39d397 CM |
2017 | copy_extent_buffer(right, left, btrfs_item_nr_offset(0), |
2018 | btrfs_item_nr_offset(left_nritems - push_items), | |
2019 | push_items * sizeof(struct btrfs_item)); | |
00ec4c51 CM |
2020 | |
2021 | /* update the item pointers */ | |
7518a238 | 2022 | right_nritems += push_items; |
5f39d397 | 2023 | btrfs_set_header_nritems(right, right_nritems); |
123abc88 | 2024 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
7518a238 | 2025 | for (i = 0; i < right_nritems; i++) { |
5f39d397 | 2026 | item = btrfs_item_nr(right, i); |
db94535d CM |
2027 | if (!right->map_token) { |
2028 | map_extent_buffer(right, (unsigned long)item, | |
2029 | sizeof(struct btrfs_item), | |
2030 | &right->map_token, &right->kaddr, | |
2031 | &right->map_start, &right->map_len, | |
2032 | KM_USER1); | |
2033 | } | |
2034 | push_space -= btrfs_item_size(right, item); | |
2035 | btrfs_set_item_offset(right, item, push_space); | |
2036 | } | |
2037 | ||
2038 | if (right->map_token) { | |
2039 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
2040 | right->map_token = NULL; | |
00ec4c51 | 2041 | } |
7518a238 | 2042 | left_nritems -= push_items; |
5f39d397 | 2043 | btrfs_set_header_nritems(left, left_nritems); |
00ec4c51 | 2044 | |
34a38218 CM |
2045 | if (left_nritems) |
2046 | btrfs_mark_buffer_dirty(left); | |
5f39d397 | 2047 | btrfs_mark_buffer_dirty(right); |
a429e513 | 2048 | |
5f39d397 CM |
2049 | btrfs_item_key(right, &disk_key, 0); |
2050 | btrfs_set_node_key(upper, &disk_key, slot + 1); | |
d6025579 | 2051 | btrfs_mark_buffer_dirty(upper); |
02217ed2 | 2052 | |
00ec4c51 | 2053 | /* then fixup the leaf pointer in the path */ |
7518a238 CM |
2054 | if (path->slots[0] >= left_nritems) { |
2055 | path->slots[0] -= left_nritems; | |
925baedd CM |
2056 | if (btrfs_header_nritems(path->nodes[0]) == 0) |
2057 | clean_tree_block(trans, root, path->nodes[0]); | |
2058 | btrfs_tree_unlock(path->nodes[0]); | |
5f39d397 CM |
2059 | free_extent_buffer(path->nodes[0]); |
2060 | path->nodes[0] = right; | |
00ec4c51 CM |
2061 | path->slots[1] += 1; |
2062 | } else { | |
925baedd | 2063 | btrfs_tree_unlock(right); |
5f39d397 | 2064 | free_extent_buffer(right); |
00ec4c51 CM |
2065 | } |
2066 | return 0; | |
925baedd CM |
2067 | |
2068 | out_unlock: | |
2069 | btrfs_tree_unlock(right); | |
2070 | free_extent_buffer(right); | |
2071 | return 1; | |
00ec4c51 | 2072 | } |
925baedd | 2073 | |
74123bd7 CM |
2074 | /* |
2075 | * push some data in the path leaf to the left, trying to free up at | |
2076 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
2077 | */ | |
e089f05c | 2078 | static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root |
34a38218 CM |
2079 | *root, struct btrfs_path *path, int data_size, |
2080 | int empty) | |
be0e5c09 | 2081 | { |
5f39d397 CM |
2082 | struct btrfs_disk_key disk_key; |
2083 | struct extent_buffer *right = path->nodes[0]; | |
2084 | struct extent_buffer *left; | |
be0e5c09 CM |
2085 | int slot; |
2086 | int i; | |
2087 | int free_space; | |
2088 | int push_space = 0; | |
2089 | int push_items = 0; | |
0783fcfc | 2090 | struct btrfs_item *item; |
7518a238 | 2091 | u32 old_left_nritems; |
5f39d397 | 2092 | u32 right_nritems; |
34a38218 | 2093 | u32 nr; |
aa5d6bed CM |
2094 | int ret = 0; |
2095 | int wret; | |
db94535d CM |
2096 | u32 this_item_size; |
2097 | u32 old_left_item_size; | |
be0e5c09 CM |
2098 | |
2099 | slot = path->slots[1]; | |
5f39d397 | 2100 | if (slot == 0) |
be0e5c09 | 2101 | return 1; |
5f39d397 | 2102 | if (!path->nodes[1]) |
be0e5c09 | 2103 | return 1; |
5f39d397 | 2104 | |
3685f791 CM |
2105 | right_nritems = btrfs_header_nritems(right); |
2106 | if (right_nritems == 0) { | |
2107 | return 1; | |
2108 | } | |
2109 | ||
a2135011 CM |
2110 | WARN_ON(!btrfs_tree_locked(path->nodes[1])); |
2111 | ||
ca7a79ad | 2112 | left = read_node_slot(root, path->nodes[1], slot - 1); |
925baedd | 2113 | btrfs_tree_lock(left); |
123abc88 | 2114 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 2115 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
925baedd CM |
2116 | ret = 1; |
2117 | goto out; | |
be0e5c09 | 2118 | } |
02217ed2 CM |
2119 | |
2120 | /* cow and double check */ | |
5f39d397 | 2121 | ret = btrfs_cow_block(trans, root, left, |
65b51a00 | 2122 | path->nodes[1], slot - 1, &left, 0); |
54aa1f4d CM |
2123 | if (ret) { |
2124 | /* we hit -ENOSPC, but it isn't fatal here */ | |
925baedd CM |
2125 | ret = 1; |
2126 | goto out; | |
54aa1f4d | 2127 | } |
3685f791 | 2128 | |
123abc88 | 2129 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 2130 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
925baedd CM |
2131 | ret = 1; |
2132 | goto out; | |
02217ed2 CM |
2133 | } |
2134 | ||
34a38218 CM |
2135 | if (empty) |
2136 | nr = right_nritems; | |
2137 | else | |
2138 | nr = right_nritems - 1; | |
2139 | ||
2140 | for (i = 0; i < nr; i++) { | |
5f39d397 | 2141 | item = btrfs_item_nr(right, i); |
db94535d CM |
2142 | if (!right->map_token) { |
2143 | map_extent_buffer(right, (unsigned long)item, | |
2144 | sizeof(struct btrfs_item), | |
2145 | &right->map_token, &right->kaddr, | |
2146 | &right->map_start, &right->map_len, | |
2147 | KM_USER1); | |
2148 | } | |
2149 | ||
be0e5c09 CM |
2150 | if (path->slots[0] == i) |
2151 | push_space += data_size + sizeof(*item); | |
db94535d CM |
2152 | |
2153 | this_item_size = btrfs_item_size(right, item); | |
2154 | if (this_item_size + sizeof(*item) + push_space > free_space) | |
be0e5c09 | 2155 | break; |
db94535d | 2156 | |
be0e5c09 | 2157 | push_items++; |
db94535d CM |
2158 | push_space += this_item_size + sizeof(*item); |
2159 | } | |
2160 | ||
2161 | if (right->map_token) { | |
2162 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
2163 | right->map_token = NULL; | |
be0e5c09 | 2164 | } |
db94535d | 2165 | |
be0e5c09 | 2166 | if (push_items == 0) { |
925baedd CM |
2167 | ret = 1; |
2168 | goto out; | |
be0e5c09 | 2169 | } |
34a38218 | 2170 | if (!empty && push_items == btrfs_header_nritems(right)) |
a429e513 | 2171 | WARN_ON(1); |
5f39d397 | 2172 | |
be0e5c09 | 2173 | /* push data from right to left */ |
5f39d397 CM |
2174 | copy_extent_buffer(left, right, |
2175 | btrfs_item_nr_offset(btrfs_header_nritems(left)), | |
2176 | btrfs_item_nr_offset(0), | |
2177 | push_items * sizeof(struct btrfs_item)); | |
2178 | ||
123abc88 | 2179 | push_space = BTRFS_LEAF_DATA_SIZE(root) - |
5f39d397 CM |
2180 | btrfs_item_offset_nr(right, push_items -1); |
2181 | ||
2182 | copy_extent_buffer(left, right, btrfs_leaf_data(left) + | |
d6025579 CM |
2183 | leaf_data_end(root, left) - push_space, |
2184 | btrfs_leaf_data(right) + | |
5f39d397 | 2185 | btrfs_item_offset_nr(right, push_items - 1), |
d6025579 | 2186 | push_space); |
5f39d397 | 2187 | old_left_nritems = btrfs_header_nritems(left); |
eb60ceac CM |
2188 | BUG_ON(old_left_nritems < 0); |
2189 | ||
db94535d | 2190 | old_left_item_size = btrfs_item_offset_nr(left, old_left_nritems - 1); |
0783fcfc | 2191 | for (i = old_left_nritems; i < old_left_nritems + push_items; i++) { |
5f39d397 | 2192 | u32 ioff; |
db94535d | 2193 | |
5f39d397 | 2194 | item = btrfs_item_nr(left, i); |
db94535d CM |
2195 | if (!left->map_token) { |
2196 | map_extent_buffer(left, (unsigned long)item, | |
2197 | sizeof(struct btrfs_item), | |
2198 | &left->map_token, &left->kaddr, | |
2199 | &left->map_start, &left->map_len, | |
2200 | KM_USER1); | |
2201 | } | |
2202 | ||
5f39d397 CM |
2203 | ioff = btrfs_item_offset(left, item); |
2204 | btrfs_set_item_offset(left, item, | |
db94535d | 2205 | ioff - (BTRFS_LEAF_DATA_SIZE(root) - old_left_item_size)); |
be0e5c09 | 2206 | } |
5f39d397 | 2207 | btrfs_set_header_nritems(left, old_left_nritems + push_items); |
db94535d CM |
2208 | if (left->map_token) { |
2209 | unmap_extent_buffer(left, left->map_token, KM_USER1); | |
2210 | left->map_token = NULL; | |
2211 | } | |
be0e5c09 CM |
2212 | |
2213 | /* fixup right node */ | |
34a38218 CM |
2214 | if (push_items > right_nritems) { |
2215 | printk("push items %d nr %u\n", push_items, right_nritems); | |
2216 | WARN_ON(1); | |
2217 | } | |
2218 | ||
2219 | if (push_items < right_nritems) { | |
2220 | push_space = btrfs_item_offset_nr(right, push_items - 1) - | |
2221 | leaf_data_end(root, right); | |
2222 | memmove_extent_buffer(right, btrfs_leaf_data(right) + | |
2223 | BTRFS_LEAF_DATA_SIZE(root) - push_space, | |
2224 | btrfs_leaf_data(right) + | |
2225 | leaf_data_end(root, right), push_space); | |
2226 | ||
2227 | memmove_extent_buffer(right, btrfs_item_nr_offset(0), | |
5f39d397 CM |
2228 | btrfs_item_nr_offset(push_items), |
2229 | (btrfs_header_nritems(right) - push_items) * | |
2230 | sizeof(struct btrfs_item)); | |
34a38218 | 2231 | } |
eef1c494 Y |
2232 | right_nritems -= push_items; |
2233 | btrfs_set_header_nritems(right, right_nritems); | |
123abc88 | 2234 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
5f39d397 CM |
2235 | for (i = 0; i < right_nritems; i++) { |
2236 | item = btrfs_item_nr(right, i); | |
db94535d CM |
2237 | |
2238 | if (!right->map_token) { | |
2239 | map_extent_buffer(right, (unsigned long)item, | |
2240 | sizeof(struct btrfs_item), | |
2241 | &right->map_token, &right->kaddr, | |
2242 | &right->map_start, &right->map_len, | |
2243 | KM_USER1); | |
2244 | } | |
2245 | ||
2246 | push_space = push_space - btrfs_item_size(right, item); | |
2247 | btrfs_set_item_offset(right, item, push_space); | |
2248 | } | |
2249 | if (right->map_token) { | |
2250 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
2251 | right->map_token = NULL; | |
be0e5c09 | 2252 | } |
eb60ceac | 2253 | |
5f39d397 | 2254 | btrfs_mark_buffer_dirty(left); |
34a38218 CM |
2255 | if (right_nritems) |
2256 | btrfs_mark_buffer_dirty(right); | |
098f59c2 | 2257 | |
5f39d397 CM |
2258 | btrfs_item_key(right, &disk_key, 0); |
2259 | wret = fixup_low_keys(trans, root, path, &disk_key, 1); | |
aa5d6bed CM |
2260 | if (wret) |
2261 | ret = wret; | |
be0e5c09 CM |
2262 | |
2263 | /* then fixup the leaf pointer in the path */ | |
2264 | if (path->slots[0] < push_items) { | |
2265 | path->slots[0] += old_left_nritems; | |
925baedd CM |
2266 | if (btrfs_header_nritems(path->nodes[0]) == 0) |
2267 | clean_tree_block(trans, root, path->nodes[0]); | |
2268 | btrfs_tree_unlock(path->nodes[0]); | |
5f39d397 CM |
2269 | free_extent_buffer(path->nodes[0]); |
2270 | path->nodes[0] = left; | |
be0e5c09 CM |
2271 | path->slots[1] -= 1; |
2272 | } else { | |
925baedd | 2273 | btrfs_tree_unlock(left); |
5f39d397 | 2274 | free_extent_buffer(left); |
be0e5c09 CM |
2275 | path->slots[0] -= push_items; |
2276 | } | |
eb60ceac | 2277 | BUG_ON(path->slots[0] < 0); |
aa5d6bed | 2278 | return ret; |
925baedd CM |
2279 | out: |
2280 | btrfs_tree_unlock(left); | |
2281 | free_extent_buffer(left); | |
2282 | return ret; | |
be0e5c09 CM |
2283 | } |
2284 | ||
74123bd7 CM |
2285 | /* |
2286 | * split the path's leaf in two, making sure there is at least data_size | |
2287 | * available for the resulting leaf level of the path. | |
aa5d6bed CM |
2288 | * |
2289 | * returns 0 if all went well and < 0 on failure. | |
74123bd7 | 2290 | */ |
e02119d5 CM |
2291 | static noinline int split_leaf(struct btrfs_trans_handle *trans, |
2292 | struct btrfs_root *root, | |
2293 | struct btrfs_key *ins_key, | |
2294 | struct btrfs_path *path, int data_size, | |
2295 | int extend) | |
be0e5c09 | 2296 | { |
7bb86316 | 2297 | u64 root_gen; |
5f39d397 | 2298 | struct extent_buffer *l; |
7518a238 | 2299 | u32 nritems; |
eb60ceac CM |
2300 | int mid; |
2301 | int slot; | |
5f39d397 | 2302 | struct extent_buffer *right; |
0783fcfc | 2303 | int space_needed = data_size + sizeof(struct btrfs_item); |
be0e5c09 CM |
2304 | int data_copy_size; |
2305 | int rt_data_off; | |
2306 | int i; | |
d4dbff95 | 2307 | int ret = 0; |
aa5d6bed | 2308 | int wret; |
cc0c5538 CM |
2309 | int double_split; |
2310 | int num_doubles = 0; | |
d4dbff95 | 2311 | struct btrfs_disk_key disk_key; |
aa5d6bed | 2312 | |
cc0c5538 CM |
2313 | if (extend) |
2314 | space_needed = data_size; | |
2315 | ||
7bb86316 CM |
2316 | if (root->ref_cows) |
2317 | root_gen = trans->transid; | |
2318 | else | |
2319 | root_gen = 0; | |
2320 | ||
40689478 | 2321 | /* first try to make some room by pushing left and right */ |
3685f791 | 2322 | if (ins_key->type != BTRFS_DIR_ITEM_KEY) { |
34a38218 | 2323 | wret = push_leaf_right(trans, root, path, data_size, 0); |
3685f791 | 2324 | if (wret < 0) { |
eaee50e8 | 2325 | return wret; |
3685f791 CM |
2326 | } |
2327 | if (wret) { | |
34a38218 | 2328 | wret = push_leaf_left(trans, root, path, data_size, 0); |
3685f791 CM |
2329 | if (wret < 0) |
2330 | return wret; | |
2331 | } | |
2332 | l = path->nodes[0]; | |
aa5d6bed | 2333 | |
3685f791 | 2334 | /* did the pushes work? */ |
cc0c5538 | 2335 | if (btrfs_leaf_free_space(root, l) >= space_needed) |
3685f791 | 2336 | return 0; |
3326d1b0 | 2337 | } |
aa5d6bed | 2338 | |
5c680ed6 | 2339 | if (!path->nodes[1]) { |
e089f05c | 2340 | ret = insert_new_root(trans, root, path, 1); |
5c680ed6 CM |
2341 | if (ret) |
2342 | return ret; | |
2343 | } | |
cc0c5538 CM |
2344 | again: |
2345 | double_split = 0; | |
2346 | l = path->nodes[0]; | |
eb60ceac | 2347 | slot = path->slots[0]; |
5f39d397 | 2348 | nritems = btrfs_header_nritems(l); |
eb60ceac | 2349 | mid = (nritems + 1)/ 2; |
54aa1f4d | 2350 | |
7bb86316 CM |
2351 | btrfs_item_key(l, &disk_key, 0); |
2352 | ||
925baedd | 2353 | right = btrfs_alloc_free_block(trans, root, root->leafsize, |
7bb86316 CM |
2354 | root->root_key.objectid, |
2355 | root_gen, disk_key.objectid, 0, | |
2356 | l->start, 0); | |
cea9e445 CM |
2357 | if (IS_ERR(right)) { |
2358 | BUG_ON(1); | |
5f39d397 | 2359 | return PTR_ERR(right); |
cea9e445 | 2360 | } |
5f39d397 CM |
2361 | |
2362 | memset_extent_buffer(right, 0, 0, sizeof(struct btrfs_header)); | |
db94535d | 2363 | btrfs_set_header_bytenr(right, right->start); |
5f39d397 CM |
2364 | btrfs_set_header_generation(right, trans->transid); |
2365 | btrfs_set_header_owner(right, root->root_key.objectid); | |
2366 | btrfs_set_header_level(right, 0); | |
2367 | write_extent_buffer(right, root->fs_info->fsid, | |
2368 | (unsigned long)btrfs_header_fsid(right), | |
2369 | BTRFS_FSID_SIZE); | |
e17cade2 CM |
2370 | |
2371 | write_extent_buffer(right, root->fs_info->chunk_tree_uuid, | |
2372 | (unsigned long)btrfs_header_chunk_tree_uuid(right), | |
2373 | BTRFS_UUID_SIZE); | |
d4dbff95 CM |
2374 | if (mid <= slot) { |
2375 | if (nritems == 1 || | |
2376 | leaf_space_used(l, mid, nritems - mid) + space_needed > | |
2377 | BTRFS_LEAF_DATA_SIZE(root)) { | |
2378 | if (slot >= nritems) { | |
2379 | btrfs_cpu_key_to_disk(&disk_key, ins_key); | |
5f39d397 | 2380 | btrfs_set_header_nritems(right, 0); |
d4dbff95 | 2381 | wret = insert_ptr(trans, root, path, |
db94535d | 2382 | &disk_key, right->start, |
d4dbff95 CM |
2383 | path->slots[1] + 1, 1); |
2384 | if (wret) | |
2385 | ret = wret; | |
925baedd CM |
2386 | |
2387 | btrfs_tree_unlock(path->nodes[0]); | |
5f39d397 CM |
2388 | free_extent_buffer(path->nodes[0]); |
2389 | path->nodes[0] = right; | |
d4dbff95 CM |
2390 | path->slots[0] = 0; |
2391 | path->slots[1] += 1; | |
0ef8b242 | 2392 | btrfs_mark_buffer_dirty(right); |
d4dbff95 CM |
2393 | return ret; |
2394 | } | |
2395 | mid = slot; | |
3326d1b0 CM |
2396 | if (mid != nritems && |
2397 | leaf_space_used(l, mid, nritems - mid) + | |
2398 | space_needed > BTRFS_LEAF_DATA_SIZE(root)) { | |
2399 | double_split = 1; | |
2400 | } | |
d4dbff95 CM |
2401 | } |
2402 | } else { | |
2403 | if (leaf_space_used(l, 0, mid + 1) + space_needed > | |
2404 | BTRFS_LEAF_DATA_SIZE(root)) { | |
cc0c5538 | 2405 | if (!extend && slot == 0) { |
d4dbff95 | 2406 | btrfs_cpu_key_to_disk(&disk_key, ins_key); |
5f39d397 | 2407 | btrfs_set_header_nritems(right, 0); |
d4dbff95 CM |
2408 | wret = insert_ptr(trans, root, path, |
2409 | &disk_key, | |
db94535d | 2410 | right->start, |
098f59c2 | 2411 | path->slots[1], 1); |
d4dbff95 CM |
2412 | if (wret) |
2413 | ret = wret; | |
925baedd | 2414 | btrfs_tree_unlock(path->nodes[0]); |
5f39d397 CM |
2415 | free_extent_buffer(path->nodes[0]); |
2416 | path->nodes[0] = right; | |
d4dbff95 | 2417 | path->slots[0] = 0; |
a429e513 CM |
2418 | if (path->slots[1] == 0) { |
2419 | wret = fixup_low_keys(trans, root, | |
2420 | path, &disk_key, 1); | |
2421 | if (wret) | |
2422 | ret = wret; | |
2423 | } | |
0ef8b242 | 2424 | btrfs_mark_buffer_dirty(right); |
d4dbff95 | 2425 | return ret; |
cc0c5538 CM |
2426 | } else if (extend && slot == 0) { |
2427 | mid = 1; | |
2428 | } else { | |
2429 | mid = slot; | |
2430 | if (mid != nritems && | |
2431 | leaf_space_used(l, mid, nritems - mid) + | |
2432 | space_needed > BTRFS_LEAF_DATA_SIZE(root)) { | |
2433 | double_split = 1; | |
2434 | } | |
5ee78ac7 | 2435 | } |
d4dbff95 CM |
2436 | } |
2437 | } | |
5f39d397 CM |
2438 | nritems = nritems - mid; |
2439 | btrfs_set_header_nritems(right, nritems); | |
2440 | data_copy_size = btrfs_item_end_nr(l, mid) - leaf_data_end(root, l); | |
2441 | ||
2442 | copy_extent_buffer(right, l, btrfs_item_nr_offset(0), | |
2443 | btrfs_item_nr_offset(mid), | |
2444 | nritems * sizeof(struct btrfs_item)); | |
2445 | ||
2446 | copy_extent_buffer(right, l, | |
d6025579 CM |
2447 | btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - |
2448 | data_copy_size, btrfs_leaf_data(l) + | |
2449 | leaf_data_end(root, l), data_copy_size); | |
5f39d397 | 2450 | |
123abc88 | 2451 | rt_data_off = BTRFS_LEAF_DATA_SIZE(root) - |
5f39d397 | 2452 | btrfs_item_end_nr(l, mid); |
74123bd7 | 2453 | |
5f39d397 CM |
2454 | for (i = 0; i < nritems; i++) { |
2455 | struct btrfs_item *item = btrfs_item_nr(right, i); | |
db94535d CM |
2456 | u32 ioff; |
2457 | ||
2458 | if (!right->map_token) { | |
2459 | map_extent_buffer(right, (unsigned long)item, | |
2460 | sizeof(struct btrfs_item), | |
2461 | &right->map_token, &right->kaddr, | |
2462 | &right->map_start, &right->map_len, | |
2463 | KM_USER1); | |
2464 | } | |
2465 | ||
2466 | ioff = btrfs_item_offset(right, item); | |
5f39d397 | 2467 | btrfs_set_item_offset(right, item, ioff + rt_data_off); |
0783fcfc | 2468 | } |
74123bd7 | 2469 | |
db94535d CM |
2470 | if (right->map_token) { |
2471 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
2472 | right->map_token = NULL; | |
2473 | } | |
2474 | ||
5f39d397 | 2475 | btrfs_set_header_nritems(l, mid); |
aa5d6bed | 2476 | ret = 0; |
5f39d397 | 2477 | btrfs_item_key(right, &disk_key, 0); |
db94535d CM |
2478 | wret = insert_ptr(trans, root, path, &disk_key, right->start, |
2479 | path->slots[1] + 1, 1); | |
aa5d6bed CM |
2480 | if (wret) |
2481 | ret = wret; | |
5f39d397 CM |
2482 | |
2483 | btrfs_mark_buffer_dirty(right); | |
2484 | btrfs_mark_buffer_dirty(l); | |
eb60ceac | 2485 | BUG_ON(path->slots[0] != slot); |
5f39d397 | 2486 | |
be0e5c09 | 2487 | if (mid <= slot) { |
925baedd | 2488 | btrfs_tree_unlock(path->nodes[0]); |
5f39d397 CM |
2489 | free_extent_buffer(path->nodes[0]); |
2490 | path->nodes[0] = right; | |
be0e5c09 CM |
2491 | path->slots[0] -= mid; |
2492 | path->slots[1] += 1; | |
925baedd CM |
2493 | } else { |
2494 | btrfs_tree_unlock(right); | |
5f39d397 | 2495 | free_extent_buffer(right); |
925baedd | 2496 | } |
5f39d397 | 2497 | |
eb60ceac | 2498 | BUG_ON(path->slots[0] < 0); |
d4dbff95 | 2499 | |
cc0c5538 CM |
2500 | if (double_split) { |
2501 | BUG_ON(num_doubles != 0); | |
2502 | num_doubles++; | |
2503 | goto again; | |
a429e513 | 2504 | } |
be0e5c09 CM |
2505 | return ret; |
2506 | } | |
2507 | ||
b18c6685 CM |
2508 | int btrfs_truncate_item(struct btrfs_trans_handle *trans, |
2509 | struct btrfs_root *root, | |
2510 | struct btrfs_path *path, | |
179e29e4 | 2511 | u32 new_size, int from_end) |
b18c6685 CM |
2512 | { |
2513 | int ret = 0; | |
2514 | int slot; | |
2515 | int slot_orig; | |
5f39d397 CM |
2516 | struct extent_buffer *leaf; |
2517 | struct btrfs_item *item; | |
b18c6685 CM |
2518 | u32 nritems; |
2519 | unsigned int data_end; | |
2520 | unsigned int old_data_start; | |
2521 | unsigned int old_size; | |
2522 | unsigned int size_diff; | |
2523 | int i; | |
2524 | ||
2525 | slot_orig = path->slots[0]; | |
5f39d397 | 2526 | leaf = path->nodes[0]; |
179e29e4 CM |
2527 | slot = path->slots[0]; |
2528 | ||
2529 | old_size = btrfs_item_size_nr(leaf, slot); | |
2530 | if (old_size == new_size) | |
2531 | return 0; | |
b18c6685 | 2532 | |
5f39d397 | 2533 | nritems = btrfs_header_nritems(leaf); |
b18c6685 CM |
2534 | data_end = leaf_data_end(root, leaf); |
2535 | ||
5f39d397 | 2536 | old_data_start = btrfs_item_offset_nr(leaf, slot); |
179e29e4 | 2537 | |
b18c6685 CM |
2538 | size_diff = old_size - new_size; |
2539 | ||
2540 | BUG_ON(slot < 0); | |
2541 | BUG_ON(slot >= nritems); | |
2542 | ||
2543 | /* | |
2544 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
2545 | */ | |
2546 | /* first correct the data pointers */ | |
2547 | for (i = slot; i < nritems; i++) { | |
5f39d397 CM |
2548 | u32 ioff; |
2549 | item = btrfs_item_nr(leaf, i); | |
db94535d CM |
2550 | |
2551 | if (!leaf->map_token) { | |
2552 | map_extent_buffer(leaf, (unsigned long)item, | |
2553 | sizeof(struct btrfs_item), | |
2554 | &leaf->map_token, &leaf->kaddr, | |
2555 | &leaf->map_start, &leaf->map_len, | |
2556 | KM_USER1); | |
2557 | } | |
2558 | ||
5f39d397 CM |
2559 | ioff = btrfs_item_offset(leaf, item); |
2560 | btrfs_set_item_offset(leaf, item, ioff + size_diff); | |
b18c6685 | 2561 | } |
db94535d CM |
2562 | |
2563 | if (leaf->map_token) { | |
2564 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
2565 | leaf->map_token = NULL; | |
2566 | } | |
2567 | ||
b18c6685 | 2568 | /* shift the data */ |
179e29e4 CM |
2569 | if (from_end) { |
2570 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
2571 | data_end + size_diff, btrfs_leaf_data(leaf) + | |
2572 | data_end, old_data_start + new_size - data_end); | |
2573 | } else { | |
2574 | struct btrfs_disk_key disk_key; | |
2575 | u64 offset; | |
2576 | ||
2577 | btrfs_item_key(leaf, &disk_key, slot); | |
2578 | ||
2579 | if (btrfs_disk_key_type(&disk_key) == BTRFS_EXTENT_DATA_KEY) { | |
2580 | unsigned long ptr; | |
2581 | struct btrfs_file_extent_item *fi; | |
2582 | ||
2583 | fi = btrfs_item_ptr(leaf, slot, | |
2584 | struct btrfs_file_extent_item); | |
2585 | fi = (struct btrfs_file_extent_item *)( | |
2586 | (unsigned long)fi - size_diff); | |
2587 | ||
2588 | if (btrfs_file_extent_type(leaf, fi) == | |
2589 | BTRFS_FILE_EXTENT_INLINE) { | |
2590 | ptr = btrfs_item_ptr_offset(leaf, slot); | |
2591 | memmove_extent_buffer(leaf, ptr, | |
2592 | (unsigned long)fi, | |
2593 | offsetof(struct btrfs_file_extent_item, | |
2594 | disk_bytenr)); | |
2595 | } | |
2596 | } | |
2597 | ||
2598 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
2599 | data_end + size_diff, btrfs_leaf_data(leaf) + | |
2600 | data_end, old_data_start - data_end); | |
2601 | ||
2602 | offset = btrfs_disk_key_offset(&disk_key); | |
2603 | btrfs_set_disk_key_offset(&disk_key, offset + size_diff); | |
2604 | btrfs_set_item_key(leaf, &disk_key, slot); | |
2605 | if (slot == 0) | |
2606 | fixup_low_keys(trans, root, path, &disk_key, 1); | |
2607 | } | |
5f39d397 CM |
2608 | |
2609 | item = btrfs_item_nr(leaf, slot); | |
2610 | btrfs_set_item_size(leaf, item, new_size); | |
2611 | btrfs_mark_buffer_dirty(leaf); | |
b18c6685 CM |
2612 | |
2613 | ret = 0; | |
5f39d397 CM |
2614 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
2615 | btrfs_print_leaf(root, leaf); | |
b18c6685 | 2616 | BUG(); |
5f39d397 | 2617 | } |
b18c6685 CM |
2618 | return ret; |
2619 | } | |
2620 | ||
5f39d397 CM |
2621 | int btrfs_extend_item(struct btrfs_trans_handle *trans, |
2622 | struct btrfs_root *root, struct btrfs_path *path, | |
2623 | u32 data_size) | |
6567e837 CM |
2624 | { |
2625 | int ret = 0; | |
2626 | int slot; | |
2627 | int slot_orig; | |
5f39d397 CM |
2628 | struct extent_buffer *leaf; |
2629 | struct btrfs_item *item; | |
6567e837 CM |
2630 | u32 nritems; |
2631 | unsigned int data_end; | |
2632 | unsigned int old_data; | |
2633 | unsigned int old_size; | |
2634 | int i; | |
2635 | ||
2636 | slot_orig = path->slots[0]; | |
5f39d397 | 2637 | leaf = path->nodes[0]; |
6567e837 | 2638 | |
5f39d397 | 2639 | nritems = btrfs_header_nritems(leaf); |
6567e837 CM |
2640 | data_end = leaf_data_end(root, leaf); |
2641 | ||
5f39d397 CM |
2642 | if (btrfs_leaf_free_space(root, leaf) < data_size) { |
2643 | btrfs_print_leaf(root, leaf); | |
6567e837 | 2644 | BUG(); |
5f39d397 | 2645 | } |
6567e837 | 2646 | slot = path->slots[0]; |
5f39d397 | 2647 | old_data = btrfs_item_end_nr(leaf, slot); |
6567e837 CM |
2648 | |
2649 | BUG_ON(slot < 0); | |
3326d1b0 CM |
2650 | if (slot >= nritems) { |
2651 | btrfs_print_leaf(root, leaf); | |
2652 | printk("slot %d too large, nritems %d\n", slot, nritems); | |
2653 | BUG_ON(1); | |
2654 | } | |
6567e837 CM |
2655 | |
2656 | /* | |
2657 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
2658 | */ | |
2659 | /* first correct the data pointers */ | |
2660 | for (i = slot; i < nritems; i++) { | |
5f39d397 CM |
2661 | u32 ioff; |
2662 | item = btrfs_item_nr(leaf, i); | |
db94535d CM |
2663 | |
2664 | if (!leaf->map_token) { | |
2665 | map_extent_buffer(leaf, (unsigned long)item, | |
2666 | sizeof(struct btrfs_item), | |
2667 | &leaf->map_token, &leaf->kaddr, | |
2668 | &leaf->map_start, &leaf->map_len, | |
2669 | KM_USER1); | |
2670 | } | |
5f39d397 CM |
2671 | ioff = btrfs_item_offset(leaf, item); |
2672 | btrfs_set_item_offset(leaf, item, ioff - data_size); | |
6567e837 | 2673 | } |
5f39d397 | 2674 | |
db94535d CM |
2675 | if (leaf->map_token) { |
2676 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
2677 | leaf->map_token = NULL; | |
2678 | } | |
2679 | ||
6567e837 | 2680 | /* shift the data */ |
5f39d397 | 2681 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
6567e837 CM |
2682 | data_end - data_size, btrfs_leaf_data(leaf) + |
2683 | data_end, old_data - data_end); | |
5f39d397 | 2684 | |
6567e837 | 2685 | data_end = old_data; |
5f39d397 CM |
2686 | old_size = btrfs_item_size_nr(leaf, slot); |
2687 | item = btrfs_item_nr(leaf, slot); | |
2688 | btrfs_set_item_size(leaf, item, old_size + data_size); | |
2689 | btrfs_mark_buffer_dirty(leaf); | |
6567e837 CM |
2690 | |
2691 | ret = 0; | |
5f39d397 CM |
2692 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
2693 | btrfs_print_leaf(root, leaf); | |
6567e837 | 2694 | BUG(); |
5f39d397 | 2695 | } |
6567e837 CM |
2696 | return ret; |
2697 | } | |
2698 | ||
74123bd7 CM |
2699 | /* |
2700 | * Given a key and some data, insert an item into the tree. | |
2701 | * This does all the path init required, making room in the tree if needed. | |
2702 | */ | |
9c58309d | 2703 | int btrfs_insert_empty_items(struct btrfs_trans_handle *trans, |
5f39d397 CM |
2704 | struct btrfs_root *root, |
2705 | struct btrfs_path *path, | |
9c58309d CM |
2706 | struct btrfs_key *cpu_key, u32 *data_size, |
2707 | int nr) | |
be0e5c09 | 2708 | { |
5f39d397 CM |
2709 | struct extent_buffer *leaf; |
2710 | struct btrfs_item *item; | |
aa5d6bed | 2711 | int ret = 0; |
be0e5c09 | 2712 | int slot; |
eb60ceac | 2713 | int slot_orig; |
9c58309d | 2714 | int i; |
7518a238 | 2715 | u32 nritems; |
9c58309d CM |
2716 | u32 total_size = 0; |
2717 | u32 total_data = 0; | |
be0e5c09 | 2718 | unsigned int data_end; |
e2fa7227 CM |
2719 | struct btrfs_disk_key disk_key; |
2720 | ||
9c58309d CM |
2721 | for (i = 0; i < nr; i++) { |
2722 | total_data += data_size[i]; | |
2723 | } | |
be0e5c09 | 2724 | |
7b128766 | 2725 | total_size = total_data + (nr * sizeof(struct btrfs_item)); |
9c58309d | 2726 | ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1); |
eb60ceac | 2727 | if (ret == 0) { |
f0930a37 | 2728 | return -EEXIST; |
aa5d6bed | 2729 | } |
ed2ff2cb CM |
2730 | if (ret < 0) |
2731 | goto out; | |
be0e5c09 | 2732 | |
62e2749e | 2733 | slot_orig = path->slots[0]; |
5f39d397 | 2734 | leaf = path->nodes[0]; |
74123bd7 | 2735 | |
5f39d397 | 2736 | nritems = btrfs_header_nritems(leaf); |
123abc88 | 2737 | data_end = leaf_data_end(root, leaf); |
eb60ceac | 2738 | |
123abc88 | 2739 | if (btrfs_leaf_free_space(root, leaf) < |
9c58309d | 2740 | sizeof(struct btrfs_item) + total_size) { |
3326d1b0 CM |
2741 | btrfs_print_leaf(root, leaf); |
2742 | printk("not enough freespace need %u have %d\n", | |
9c58309d | 2743 | total_size, btrfs_leaf_free_space(root, leaf)); |
be0e5c09 | 2744 | BUG(); |
d4dbff95 | 2745 | } |
5f39d397 | 2746 | |
62e2749e | 2747 | slot = path->slots[0]; |
eb60ceac | 2748 | BUG_ON(slot < 0); |
5f39d397 | 2749 | |
be0e5c09 CM |
2750 | if (slot != nritems) { |
2751 | int i; | |
5f39d397 | 2752 | unsigned int old_data = btrfs_item_end_nr(leaf, slot); |
be0e5c09 | 2753 | |
5f39d397 CM |
2754 | if (old_data < data_end) { |
2755 | btrfs_print_leaf(root, leaf); | |
2756 | printk("slot %d old_data %d data_end %d\n", | |
2757 | slot, old_data, data_end); | |
2758 | BUG_ON(1); | |
2759 | } | |
be0e5c09 CM |
2760 | /* |
2761 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
2762 | */ | |
2763 | /* first correct the data pointers */ | |
db94535d | 2764 | WARN_ON(leaf->map_token); |
0783fcfc | 2765 | for (i = slot; i < nritems; i++) { |
5f39d397 | 2766 | u32 ioff; |
db94535d | 2767 | |
5f39d397 | 2768 | item = btrfs_item_nr(leaf, i); |
db94535d CM |
2769 | if (!leaf->map_token) { |
2770 | map_extent_buffer(leaf, (unsigned long)item, | |
2771 | sizeof(struct btrfs_item), | |
2772 | &leaf->map_token, &leaf->kaddr, | |
2773 | &leaf->map_start, &leaf->map_len, | |
2774 | KM_USER1); | |
2775 | } | |
2776 | ||
5f39d397 | 2777 | ioff = btrfs_item_offset(leaf, item); |
9c58309d | 2778 | btrfs_set_item_offset(leaf, item, ioff - total_data); |
0783fcfc | 2779 | } |
db94535d CM |
2780 | if (leaf->map_token) { |
2781 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
2782 | leaf->map_token = NULL; | |
2783 | } | |
be0e5c09 CM |
2784 | |
2785 | /* shift the items */ | |
9c58309d | 2786 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr), |
5f39d397 | 2787 | btrfs_item_nr_offset(slot), |
d6025579 | 2788 | (nritems - slot) * sizeof(struct btrfs_item)); |
be0e5c09 CM |
2789 | |
2790 | /* shift the data */ | |
5f39d397 | 2791 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
9c58309d | 2792 | data_end - total_data, btrfs_leaf_data(leaf) + |
d6025579 | 2793 | data_end, old_data - data_end); |
be0e5c09 CM |
2794 | data_end = old_data; |
2795 | } | |
5f39d397 | 2796 | |
62e2749e | 2797 | /* setup the item for the new data */ |
9c58309d CM |
2798 | for (i = 0; i < nr; i++) { |
2799 | btrfs_cpu_key_to_disk(&disk_key, cpu_key + i); | |
2800 | btrfs_set_item_key(leaf, &disk_key, slot + i); | |
2801 | item = btrfs_item_nr(leaf, slot + i); | |
2802 | btrfs_set_item_offset(leaf, item, data_end - data_size[i]); | |
2803 | data_end -= data_size[i]; | |
2804 | btrfs_set_item_size(leaf, item, data_size[i]); | |
2805 | } | |
2806 | btrfs_set_header_nritems(leaf, nritems + nr); | |
5f39d397 | 2807 | btrfs_mark_buffer_dirty(leaf); |
aa5d6bed CM |
2808 | |
2809 | ret = 0; | |
5a01a2e3 CM |
2810 | if (slot == 0) { |
2811 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); | |
e089f05c | 2812 | ret = fixup_low_keys(trans, root, path, &disk_key, 1); |
5a01a2e3 | 2813 | } |
aa5d6bed | 2814 | |
5f39d397 CM |
2815 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
2816 | btrfs_print_leaf(root, leaf); | |
be0e5c09 | 2817 | BUG(); |
5f39d397 | 2818 | } |
ed2ff2cb | 2819 | out: |
62e2749e CM |
2820 | return ret; |
2821 | } | |
2822 | ||
2823 | /* | |
2824 | * Given a key and some data, insert an item into the tree. | |
2825 | * This does all the path init required, making room in the tree if needed. | |
2826 | */ | |
e089f05c CM |
2827 | int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root |
2828 | *root, struct btrfs_key *cpu_key, void *data, u32 | |
2829 | data_size) | |
62e2749e CM |
2830 | { |
2831 | int ret = 0; | |
2c90e5d6 | 2832 | struct btrfs_path *path; |
5f39d397 CM |
2833 | struct extent_buffer *leaf; |
2834 | unsigned long ptr; | |
62e2749e | 2835 | |
2c90e5d6 CM |
2836 | path = btrfs_alloc_path(); |
2837 | BUG_ON(!path); | |
2c90e5d6 | 2838 | ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size); |
62e2749e | 2839 | if (!ret) { |
5f39d397 CM |
2840 | leaf = path->nodes[0]; |
2841 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
2842 | write_extent_buffer(leaf, data, ptr, data_size); | |
2843 | btrfs_mark_buffer_dirty(leaf); | |
62e2749e | 2844 | } |
2c90e5d6 | 2845 | btrfs_free_path(path); |
aa5d6bed | 2846 | return ret; |
be0e5c09 CM |
2847 | } |
2848 | ||
74123bd7 | 2849 | /* |
5de08d7d | 2850 | * delete the pointer from a given node. |
74123bd7 CM |
2851 | * |
2852 | * If the delete empties a node, the node is removed from the tree, | |
2853 | * continuing all the way the root if required. The root is converted into | |
2854 | * a leaf if all the nodes are emptied. | |
2855 | */ | |
e089f05c CM |
2856 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
2857 | struct btrfs_path *path, int level, int slot) | |
be0e5c09 | 2858 | { |
5f39d397 | 2859 | struct extent_buffer *parent = path->nodes[level]; |
7518a238 | 2860 | u32 nritems; |
aa5d6bed | 2861 | int ret = 0; |
bb803951 | 2862 | int wret; |
be0e5c09 | 2863 | |
5f39d397 | 2864 | nritems = btrfs_header_nritems(parent); |
bb803951 | 2865 | if (slot != nritems -1) { |
5f39d397 CM |
2866 | memmove_extent_buffer(parent, |
2867 | btrfs_node_key_ptr_offset(slot), | |
2868 | btrfs_node_key_ptr_offset(slot + 1), | |
d6025579 CM |
2869 | sizeof(struct btrfs_key_ptr) * |
2870 | (nritems - slot - 1)); | |
bb803951 | 2871 | } |
7518a238 | 2872 | nritems--; |
5f39d397 | 2873 | btrfs_set_header_nritems(parent, nritems); |
7518a238 | 2874 | if (nritems == 0 && parent == root->node) { |
5f39d397 | 2875 | BUG_ON(btrfs_header_level(root->node) != 1); |
bb803951 | 2876 | /* just turn the root into a leaf and break */ |
5f39d397 | 2877 | btrfs_set_header_level(root->node, 0); |
bb803951 | 2878 | } else if (slot == 0) { |
5f39d397 CM |
2879 | struct btrfs_disk_key disk_key; |
2880 | ||
2881 | btrfs_node_key(parent, &disk_key, 0); | |
2882 | wret = fixup_low_keys(trans, root, path, &disk_key, level + 1); | |
0f70abe2 CM |
2883 | if (wret) |
2884 | ret = wret; | |
be0e5c09 | 2885 | } |
d6025579 | 2886 | btrfs_mark_buffer_dirty(parent); |
aa5d6bed | 2887 | return ret; |
be0e5c09 CM |
2888 | } |
2889 | ||
74123bd7 CM |
2890 | /* |
2891 | * delete the item at the leaf level in path. If that empties | |
2892 | * the leaf, remove it from the tree | |
2893 | */ | |
85e21bac CM |
2894 | int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
2895 | struct btrfs_path *path, int slot, int nr) | |
be0e5c09 | 2896 | { |
5f39d397 CM |
2897 | struct extent_buffer *leaf; |
2898 | struct btrfs_item *item; | |
85e21bac CM |
2899 | int last_off; |
2900 | int dsize = 0; | |
aa5d6bed CM |
2901 | int ret = 0; |
2902 | int wret; | |
85e21bac | 2903 | int i; |
7518a238 | 2904 | u32 nritems; |
be0e5c09 | 2905 | |
5f39d397 | 2906 | leaf = path->nodes[0]; |
85e21bac CM |
2907 | last_off = btrfs_item_offset_nr(leaf, slot + nr - 1); |
2908 | ||
2909 | for (i = 0; i < nr; i++) | |
2910 | dsize += btrfs_item_size_nr(leaf, slot + i); | |
2911 | ||
5f39d397 | 2912 | nritems = btrfs_header_nritems(leaf); |
be0e5c09 | 2913 | |
85e21bac | 2914 | if (slot + nr != nritems) { |
be0e5c09 | 2915 | int i; |
123abc88 | 2916 | int data_end = leaf_data_end(root, leaf); |
5f39d397 CM |
2917 | |
2918 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
d6025579 CM |
2919 | data_end + dsize, |
2920 | btrfs_leaf_data(leaf) + data_end, | |
85e21bac | 2921 | last_off - data_end); |
5f39d397 | 2922 | |
85e21bac | 2923 | for (i = slot + nr; i < nritems; i++) { |
5f39d397 | 2924 | u32 ioff; |
db94535d | 2925 | |
5f39d397 | 2926 | item = btrfs_item_nr(leaf, i); |
db94535d CM |
2927 | if (!leaf->map_token) { |
2928 | map_extent_buffer(leaf, (unsigned long)item, | |
2929 | sizeof(struct btrfs_item), | |
2930 | &leaf->map_token, &leaf->kaddr, | |
2931 | &leaf->map_start, &leaf->map_len, | |
2932 | KM_USER1); | |
2933 | } | |
5f39d397 CM |
2934 | ioff = btrfs_item_offset(leaf, item); |
2935 | btrfs_set_item_offset(leaf, item, ioff + dsize); | |
0783fcfc | 2936 | } |
db94535d CM |
2937 | |
2938 | if (leaf->map_token) { | |
2939 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
2940 | leaf->map_token = NULL; | |
2941 | } | |
2942 | ||
5f39d397 | 2943 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot), |
85e21bac | 2944 | btrfs_item_nr_offset(slot + nr), |
d6025579 | 2945 | sizeof(struct btrfs_item) * |
85e21bac | 2946 | (nritems - slot - nr)); |
be0e5c09 | 2947 | } |
85e21bac CM |
2948 | btrfs_set_header_nritems(leaf, nritems - nr); |
2949 | nritems -= nr; | |
5f39d397 | 2950 | |
74123bd7 | 2951 | /* delete the leaf if we've emptied it */ |
7518a238 | 2952 | if (nritems == 0) { |
5f39d397 CM |
2953 | if (leaf == root->node) { |
2954 | btrfs_set_header_level(leaf, 0); | |
9a8dd150 | 2955 | } else { |
7bb86316 | 2956 | u64 root_gen = btrfs_header_generation(path->nodes[1]); |
e089f05c | 2957 | wret = del_ptr(trans, root, path, 1, path->slots[1]); |
aa5d6bed CM |
2958 | if (wret) |
2959 | ret = wret; | |
e089f05c | 2960 | wret = btrfs_free_extent(trans, root, |
7bb86316 CM |
2961 | leaf->start, leaf->len, |
2962 | btrfs_header_owner(path->nodes[1]), | |
2963 | root_gen, 0, 0, 1); | |
0f70abe2 CM |
2964 | if (wret) |
2965 | ret = wret; | |
9a8dd150 | 2966 | } |
be0e5c09 | 2967 | } else { |
7518a238 | 2968 | int used = leaf_space_used(leaf, 0, nritems); |
aa5d6bed | 2969 | if (slot == 0) { |
5f39d397 CM |
2970 | struct btrfs_disk_key disk_key; |
2971 | ||
2972 | btrfs_item_key(leaf, &disk_key, 0); | |
e089f05c | 2973 | wret = fixup_low_keys(trans, root, path, |
5f39d397 | 2974 | &disk_key, 1); |
aa5d6bed CM |
2975 | if (wret) |
2976 | ret = wret; | |
2977 | } | |
aa5d6bed | 2978 | |
74123bd7 | 2979 | /* delete the leaf if it is mostly empty */ |
85e21bac | 2980 | if (used < BTRFS_LEAF_DATA_SIZE(root) / 4) { |
be0e5c09 CM |
2981 | /* push_leaf_left fixes the path. |
2982 | * make sure the path still points to our leaf | |
2983 | * for possible call to del_ptr below | |
2984 | */ | |
4920c9ac | 2985 | slot = path->slots[1]; |
5f39d397 CM |
2986 | extent_buffer_get(leaf); |
2987 | ||
85e21bac | 2988 | wret = push_leaf_left(trans, root, path, 1, 1); |
54aa1f4d | 2989 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed | 2990 | ret = wret; |
5f39d397 CM |
2991 | |
2992 | if (path->nodes[0] == leaf && | |
2993 | btrfs_header_nritems(leaf)) { | |
85e21bac | 2994 | wret = push_leaf_right(trans, root, path, 1, 1); |
54aa1f4d | 2995 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed CM |
2996 | ret = wret; |
2997 | } | |
5f39d397 CM |
2998 | |
2999 | if (btrfs_header_nritems(leaf) == 0) { | |
7bb86316 | 3000 | u64 root_gen; |
db94535d CM |
3001 | u64 bytenr = leaf->start; |
3002 | u32 blocksize = leaf->len; | |
5f39d397 | 3003 | |
7bb86316 CM |
3004 | root_gen = btrfs_header_generation( |
3005 | path->nodes[1]); | |
3006 | ||
e089f05c | 3007 | wret = del_ptr(trans, root, path, 1, slot); |
aa5d6bed CM |
3008 | if (wret) |
3009 | ret = wret; | |
5f39d397 CM |
3010 | |
3011 | free_extent_buffer(leaf); | |
db94535d | 3012 | wret = btrfs_free_extent(trans, root, bytenr, |
7bb86316 CM |
3013 | blocksize, |
3014 | btrfs_header_owner(path->nodes[1]), | |
3015 | root_gen, 0, 0, 1); | |
0f70abe2 CM |
3016 | if (wret) |
3017 | ret = wret; | |
5de08d7d | 3018 | } else { |
925baedd CM |
3019 | /* if we're still in the path, make sure |
3020 | * we're dirty. Otherwise, one of the | |
3021 | * push_leaf functions must have already | |
3022 | * dirtied this buffer | |
3023 | */ | |
3024 | if (path->nodes[0] == leaf) | |
3025 | btrfs_mark_buffer_dirty(leaf); | |
5f39d397 | 3026 | free_extent_buffer(leaf); |
be0e5c09 | 3027 | } |
d5719762 | 3028 | } else { |
5f39d397 | 3029 | btrfs_mark_buffer_dirty(leaf); |
be0e5c09 CM |
3030 | } |
3031 | } | |
aa5d6bed | 3032 | return ret; |
be0e5c09 CM |
3033 | } |
3034 | ||
7bb86316 | 3035 | /* |
925baedd | 3036 | * search the tree again to find a leaf with lesser keys |
7bb86316 CM |
3037 | * returns 0 if it found something or 1 if there are no lesser leaves. |
3038 | * returns < 0 on io errors. | |
3039 | */ | |
3040 | int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path) | |
3041 | { | |
925baedd CM |
3042 | struct btrfs_key key; |
3043 | struct btrfs_disk_key found_key; | |
3044 | int ret; | |
7bb86316 | 3045 | |
925baedd | 3046 | btrfs_item_key_to_cpu(path->nodes[0], &key, 0); |
7bb86316 | 3047 | |
925baedd CM |
3048 | if (key.offset > 0) |
3049 | key.offset--; | |
3050 | else if (key.type > 0) | |
3051 | key.type--; | |
3052 | else if (key.objectid > 0) | |
3053 | key.objectid--; | |
3054 | else | |
3055 | return 1; | |
7bb86316 | 3056 | |
925baedd CM |
3057 | btrfs_release_path(root, path); |
3058 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
3059 | if (ret < 0) | |
3060 | return ret; | |
3061 | btrfs_item_key(path->nodes[0], &found_key, 0); | |
3062 | ret = comp_keys(&found_key, &key); | |
3063 | if (ret < 0) | |
3064 | return 0; | |
3065 | return 1; | |
7bb86316 CM |
3066 | } |
3067 | ||
3f157a2f CM |
3068 | /* |
3069 | * A helper function to walk down the tree starting at min_key, and looking | |
3070 | * for nodes or leaves that are either in cache or have a minimum | |
3071 | * transaction id. This is used by the btree defrag code, but could | |
3072 | * also be used to search for blocks that have changed since a given | |
3073 | * transaction id. | |
3074 | * | |
3075 | * This does not cow, but it does stuff the starting key it finds back | |
3076 | * into min_key, so you can call btrfs_search_slot with cow=1 on the | |
3077 | * key and get a writable path. | |
3078 | * | |
3079 | * This does lock as it descends, and path->keep_locks should be set | |
3080 | * to 1 by the caller. | |
3081 | * | |
3082 | * This honors path->lowest_level to prevent descent past a given level | |
3083 | * of the tree. | |
3084 | * | |
3085 | * returns zero if something useful was found, < 0 on error and 1 if there | |
3086 | * was nothing in the tree that matched the search criteria. | |
3087 | */ | |
3088 | int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key, | |
e02119d5 | 3089 | struct btrfs_key *max_key, |
3f157a2f CM |
3090 | struct btrfs_path *path, int cache_only, |
3091 | u64 min_trans) | |
3092 | { | |
3093 | struct extent_buffer *cur; | |
3094 | struct btrfs_key found_key; | |
3095 | int slot; | |
9652480b | 3096 | int sret; |
3f157a2f CM |
3097 | u32 nritems; |
3098 | int level; | |
3099 | int ret = 1; | |
3100 | ||
3101 | again: | |
3102 | cur = btrfs_lock_root_node(root); | |
3103 | level = btrfs_header_level(cur); | |
e02119d5 | 3104 | WARN_ON(path->nodes[level]); |
3f157a2f CM |
3105 | path->nodes[level] = cur; |
3106 | path->locks[level] = 1; | |
3107 | ||
3108 | if (btrfs_header_generation(cur) < min_trans) { | |
3109 | ret = 1; | |
3110 | goto out; | |
3111 | } | |
3112 | while(1) { | |
3113 | nritems = btrfs_header_nritems(cur); | |
3114 | level = btrfs_header_level(cur); | |
9652480b | 3115 | sret = bin_search(cur, min_key, level, &slot); |
3f157a2f CM |
3116 | |
3117 | /* at level = 0, we're done, setup the path and exit */ | |
3118 | if (level == 0) { | |
e02119d5 CM |
3119 | if (slot >= nritems) |
3120 | goto find_next_key; | |
3f157a2f CM |
3121 | ret = 0; |
3122 | path->slots[level] = slot; | |
3123 | btrfs_item_key_to_cpu(cur, &found_key, slot); | |
3124 | goto out; | |
3125 | } | |
9652480b Y |
3126 | if (sret && slot > 0) |
3127 | slot--; | |
3f157a2f CM |
3128 | /* |
3129 | * check this node pointer against the cache_only and | |
3130 | * min_trans parameters. If it isn't in cache or is too | |
3131 | * old, skip to the next one. | |
3132 | */ | |
3133 | while(slot < nritems) { | |
3134 | u64 blockptr; | |
3135 | u64 gen; | |
3136 | struct extent_buffer *tmp; | |
e02119d5 CM |
3137 | struct btrfs_disk_key disk_key; |
3138 | ||
3f157a2f CM |
3139 | blockptr = btrfs_node_blockptr(cur, slot); |
3140 | gen = btrfs_node_ptr_generation(cur, slot); | |
3141 | if (gen < min_trans) { | |
3142 | slot++; | |
3143 | continue; | |
3144 | } | |
3145 | if (!cache_only) | |
3146 | break; | |
3147 | ||
e02119d5 CM |
3148 | if (max_key) { |
3149 | btrfs_node_key(cur, &disk_key, slot); | |
3150 | if (comp_keys(&disk_key, max_key) >= 0) { | |
3151 | ret = 1; | |
3152 | goto out; | |
3153 | } | |
3154 | } | |
3155 | ||
3f157a2f CM |
3156 | tmp = btrfs_find_tree_block(root, blockptr, |
3157 | btrfs_level_size(root, level - 1)); | |
3158 | ||
3159 | if (tmp && btrfs_buffer_uptodate(tmp, gen)) { | |
3160 | free_extent_buffer(tmp); | |
3161 | break; | |
3162 | } | |
3163 | if (tmp) | |
3164 | free_extent_buffer(tmp); | |
3165 | slot++; | |
3166 | } | |
e02119d5 | 3167 | find_next_key: |
3f157a2f CM |
3168 | /* |
3169 | * we didn't find a candidate key in this node, walk forward | |
3170 | * and find another one | |
3171 | */ | |
3172 | if (slot >= nritems) { | |
e02119d5 CM |
3173 | path->slots[level] = slot; |
3174 | sret = btrfs_find_next_key(root, path, min_key, level, | |
3f157a2f | 3175 | cache_only, min_trans); |
e02119d5 | 3176 | if (sret == 0) { |
3f157a2f CM |
3177 | btrfs_release_path(root, path); |
3178 | goto again; | |
3179 | } else { | |
3180 | goto out; | |
3181 | } | |
3182 | } | |
3183 | /* save our key for returning back */ | |
3184 | btrfs_node_key_to_cpu(cur, &found_key, slot); | |
3185 | path->slots[level] = slot; | |
3186 | if (level == path->lowest_level) { | |
3187 | ret = 0; | |
3188 | unlock_up(path, level, 1); | |
3189 | goto out; | |
3190 | } | |
3191 | cur = read_node_slot(root, cur, slot); | |
3192 | ||
3193 | btrfs_tree_lock(cur); | |
3194 | path->locks[level - 1] = 1; | |
3195 | path->nodes[level - 1] = cur; | |
3196 | unlock_up(path, level, 1); | |
3197 | } | |
3198 | out: | |
3199 | if (ret == 0) | |
3200 | memcpy(min_key, &found_key, sizeof(found_key)); | |
3201 | return ret; | |
3202 | } | |
3203 | ||
3204 | /* | |
3205 | * this is similar to btrfs_next_leaf, but does not try to preserve | |
3206 | * and fixup the path. It looks for and returns the next key in the | |
3207 | * tree based on the current path and the cache_only and min_trans | |
3208 | * parameters. | |
3209 | * | |
3210 | * 0 is returned if another key is found, < 0 if there are any errors | |
3211 | * and 1 is returned if there are no higher keys in the tree | |
3212 | * | |
3213 | * path->keep_locks should be set to 1 on the search made before | |
3214 | * calling this function. | |
3215 | */ | |
e7a84565 | 3216 | int btrfs_find_next_key(struct btrfs_root *root, struct btrfs_path *path, |
3f157a2f CM |
3217 | struct btrfs_key *key, int lowest_level, |
3218 | int cache_only, u64 min_trans) | |
e7a84565 CM |
3219 | { |
3220 | int level = lowest_level; | |
3221 | int slot; | |
3222 | struct extent_buffer *c; | |
3223 | ||
3224 | while(level < BTRFS_MAX_LEVEL) { | |
3225 | if (!path->nodes[level]) | |
3226 | return 1; | |
3227 | ||
3228 | slot = path->slots[level] + 1; | |
3229 | c = path->nodes[level]; | |
3f157a2f | 3230 | next: |
e7a84565 CM |
3231 | if (slot >= btrfs_header_nritems(c)) { |
3232 | level++; | |
3233 | if (level == BTRFS_MAX_LEVEL) { | |
3234 | return 1; | |
3235 | } | |
3236 | continue; | |
3237 | } | |
3238 | if (level == 0) | |
3239 | btrfs_item_key_to_cpu(c, key, slot); | |
3f157a2f CM |
3240 | else { |
3241 | u64 blockptr = btrfs_node_blockptr(c, slot); | |
3242 | u64 gen = btrfs_node_ptr_generation(c, slot); | |
3243 | ||
3244 | if (cache_only) { | |
3245 | struct extent_buffer *cur; | |
3246 | cur = btrfs_find_tree_block(root, blockptr, | |
3247 | btrfs_level_size(root, level - 1)); | |
3248 | if (!cur || !btrfs_buffer_uptodate(cur, gen)) { | |
3249 | slot++; | |
3250 | if (cur) | |
3251 | free_extent_buffer(cur); | |
3252 | goto next; | |
3253 | } | |
3254 | free_extent_buffer(cur); | |
3255 | } | |
3256 | if (gen < min_trans) { | |
3257 | slot++; | |
3258 | goto next; | |
3259 | } | |
e7a84565 | 3260 | btrfs_node_key_to_cpu(c, key, slot); |
3f157a2f | 3261 | } |
e7a84565 CM |
3262 | return 0; |
3263 | } | |
3264 | return 1; | |
3265 | } | |
3266 | ||
97571fd0 | 3267 | /* |
925baedd | 3268 | * search the tree again to find a leaf with greater keys |
0f70abe2 CM |
3269 | * returns 0 if it found something or 1 if there are no greater leaves. |
3270 | * returns < 0 on io errors. | |
97571fd0 | 3271 | */ |
234b63a0 | 3272 | int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) |
d97e63b6 CM |
3273 | { |
3274 | int slot; | |
3275 | int level = 1; | |
5f39d397 CM |
3276 | struct extent_buffer *c; |
3277 | struct extent_buffer *next = NULL; | |
925baedd CM |
3278 | struct btrfs_key key; |
3279 | u32 nritems; | |
3280 | int ret; | |
3281 | ||
3282 | nritems = btrfs_header_nritems(path->nodes[0]); | |
3283 | if (nritems == 0) { | |
3284 | return 1; | |
3285 | } | |
3286 | ||
3287 | btrfs_item_key_to_cpu(path->nodes[0], &key, nritems - 1); | |
3288 | ||
925baedd | 3289 | btrfs_release_path(root, path); |
a2135011 | 3290 | path->keep_locks = 1; |
925baedd CM |
3291 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
3292 | path->keep_locks = 0; | |
3293 | ||
3294 | if (ret < 0) | |
3295 | return ret; | |
3296 | ||
a2135011 | 3297 | nritems = btrfs_header_nritems(path->nodes[0]); |
168fd7d2 CM |
3298 | /* |
3299 | * by releasing the path above we dropped all our locks. A balance | |
3300 | * could have added more items next to the key that used to be | |
3301 | * at the very end of the block. So, check again here and | |
3302 | * advance the path if there are now more items available. | |
3303 | */ | |
a2135011 | 3304 | if (nritems > 0 && path->slots[0] < nritems - 1) { |
168fd7d2 | 3305 | path->slots[0]++; |
925baedd CM |
3306 | goto done; |
3307 | } | |
d97e63b6 | 3308 | |
234b63a0 | 3309 | while(level < BTRFS_MAX_LEVEL) { |
d97e63b6 | 3310 | if (!path->nodes[level]) |
0f70abe2 | 3311 | return 1; |
5f39d397 | 3312 | |
d97e63b6 CM |
3313 | slot = path->slots[level] + 1; |
3314 | c = path->nodes[level]; | |
5f39d397 | 3315 | if (slot >= btrfs_header_nritems(c)) { |
d97e63b6 | 3316 | level++; |
925baedd | 3317 | if (level == BTRFS_MAX_LEVEL) { |
7bb86316 | 3318 | return 1; |
925baedd | 3319 | } |
d97e63b6 CM |
3320 | continue; |
3321 | } | |
5f39d397 | 3322 | |
925baedd CM |
3323 | if (next) { |
3324 | btrfs_tree_unlock(next); | |
5f39d397 | 3325 | free_extent_buffer(next); |
925baedd | 3326 | } |
5f39d397 | 3327 | |
0bd40a71 CM |
3328 | if (level == 1 && (path->locks[1] || path->skip_locking) && |
3329 | path->reada) | |
01f46658 | 3330 | reada_for_search(root, path, level, slot, 0); |
5f39d397 | 3331 | |
ca7a79ad | 3332 | next = read_node_slot(root, c, slot); |
5cd57b2c CM |
3333 | if (!path->skip_locking) { |
3334 | WARN_ON(!btrfs_tree_locked(c)); | |
3335 | btrfs_tree_lock(next); | |
3336 | } | |
d97e63b6 CM |
3337 | break; |
3338 | } | |
3339 | path->slots[level] = slot; | |
3340 | while(1) { | |
3341 | level--; | |
3342 | c = path->nodes[level]; | |
925baedd CM |
3343 | if (path->locks[level]) |
3344 | btrfs_tree_unlock(c); | |
5f39d397 | 3345 | free_extent_buffer(c); |
d97e63b6 CM |
3346 | path->nodes[level] = next; |
3347 | path->slots[level] = 0; | |
a74a4b97 CM |
3348 | if (!path->skip_locking) |
3349 | path->locks[level] = 1; | |
d97e63b6 CM |
3350 | if (!level) |
3351 | break; | |
925baedd CM |
3352 | if (level == 1 && path->locks[1] && path->reada) |
3353 | reada_for_search(root, path, level, slot, 0); | |
ca7a79ad | 3354 | next = read_node_slot(root, next, 0); |
5cd57b2c CM |
3355 | if (!path->skip_locking) { |
3356 | WARN_ON(!btrfs_tree_locked(path->nodes[level])); | |
3357 | btrfs_tree_lock(next); | |
3358 | } | |
d97e63b6 | 3359 | } |
925baedd CM |
3360 | done: |
3361 | unlock_up(path, 0, 1); | |
d97e63b6 CM |
3362 | return 0; |
3363 | } | |
0b86a832 | 3364 | |
3f157a2f CM |
3365 | /* |
3366 | * this uses btrfs_prev_leaf to walk backwards in the tree, and keeps | |
3367 | * searching until it gets past min_objectid or finds an item of 'type' | |
3368 | * | |
3369 | * returns 0 if something is found, 1 if nothing was found and < 0 on error | |
3370 | */ | |
0b86a832 CM |
3371 | int btrfs_previous_item(struct btrfs_root *root, |
3372 | struct btrfs_path *path, u64 min_objectid, | |
3373 | int type) | |
3374 | { | |
3375 | struct btrfs_key found_key; | |
3376 | struct extent_buffer *leaf; | |
e02119d5 | 3377 | u32 nritems; |
0b86a832 CM |
3378 | int ret; |
3379 | ||
3380 | while(1) { | |
3381 | if (path->slots[0] == 0) { | |
3382 | ret = btrfs_prev_leaf(root, path); | |
3383 | if (ret != 0) | |
3384 | return ret; | |
3385 | } else { | |
3386 | path->slots[0]--; | |
3387 | } | |
3388 | leaf = path->nodes[0]; | |
e02119d5 CM |
3389 | nritems = btrfs_header_nritems(leaf); |
3390 | if (nritems == 0) | |
3391 | return 1; | |
3392 | if (path->slots[0] == nritems) | |
3393 | path->slots[0]--; | |
3394 | ||
0b86a832 CM |
3395 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
3396 | if (found_key.type == type) | |
3397 | return 0; | |
e02119d5 CM |
3398 | if (found_key.objectid < min_objectid) |
3399 | break; | |
3400 | if (found_key.objectid == min_objectid && | |
3401 | found_key.type < type) | |
3402 | break; | |
0b86a832 CM |
3403 | } |
3404 | return 1; | |
3405 | } |