Commit | Line | Data |
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6cbd5570 CM |
1 | /* |
2 | * Copyright (C) 2007 Oracle. All rights reserved. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public | |
6 | * License v2 as published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
11 | * General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public | |
14 | * License along with this program; if not, write to the | |
15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
16 | * Boston, MA 021110-1307, USA. | |
17 | */ | |
18 | ||
eb60ceac CM |
19 | #include "ctree.h" |
20 | #include "disk-io.h" | |
7f5c1516 | 21 | #include "transaction.h" |
9a8dd150 | 22 | |
e089f05c CM |
23 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
24 | *root, struct btrfs_path *path, int level); | |
25 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root | |
d4dbff95 CM |
26 | *root, struct btrfs_key *ins_key, |
27 | struct btrfs_path *path, int data_size); | |
e089f05c | 28 | static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root |
e20d96d6 | 29 | *root, struct buffer_head *dst, struct buffer_head |
e089f05c CM |
30 | *src); |
31 | static int balance_node_right(struct btrfs_trans_handle *trans, struct | |
e20d96d6 CM |
32 | btrfs_root *root, struct buffer_head *dst_buf, |
33 | struct buffer_head *src_buf); | |
e089f05c CM |
34 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
35 | struct btrfs_path *path, int level, int slot); | |
d97e63b6 | 36 | |
df24a2b9 | 37 | inline void btrfs_init_path(struct btrfs_path *p) |
2c90e5d6 | 38 | { |
df24a2b9 | 39 | memset(p, 0, sizeof(*p)); |
2c90e5d6 CM |
40 | } |
41 | ||
df24a2b9 | 42 | struct btrfs_path *btrfs_alloc_path(void) |
2c90e5d6 | 43 | { |
df24a2b9 CM |
44 | struct btrfs_path *path; |
45 | path = kmem_cache_alloc(btrfs_path_cachep, GFP_NOFS); | |
46 | if (path) | |
47 | btrfs_init_path(path); | |
48 | return path; | |
2c90e5d6 CM |
49 | } |
50 | ||
df24a2b9 | 51 | void btrfs_free_path(struct btrfs_path *p) |
be0e5c09 | 52 | { |
df24a2b9 CM |
53 | btrfs_release_path(NULL, p); |
54 | kmem_cache_free(btrfs_path_cachep, p); | |
be0e5c09 CM |
55 | } |
56 | ||
234b63a0 | 57 | void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p) |
eb60ceac CM |
58 | { |
59 | int i; | |
234b63a0 | 60 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
eb60ceac CM |
61 | if (!p->nodes[i]) |
62 | break; | |
234b63a0 | 63 | btrfs_block_release(root, p->nodes[i]); |
eb60ceac | 64 | } |
aa5d6bed | 65 | memset(p, 0, sizeof(*p)); |
eb60ceac CM |
66 | } |
67 | ||
e089f05c | 68 | static int btrfs_cow_block(struct btrfs_trans_handle *trans, struct btrfs_root |
e20d96d6 CM |
69 | *root, struct buffer_head *buf, struct buffer_head |
70 | *parent, int parent_slot, struct buffer_head | |
e089f05c | 71 | **cow_ret) |
02217ed2 | 72 | { |
e20d96d6 CM |
73 | struct buffer_head *cow; |
74 | struct btrfs_node *cow_node; | |
54aa1f4d | 75 | int ret; |
02217ed2 | 76 | |
ccd467d6 CM |
77 | WARN_ON(!buffer_uptodate(buf)); |
78 | if (trans->transaction != root->fs_info->running_transaction) { | |
79 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
80 | root->fs_info->running_transaction->transid); | |
81 | WARN_ON(1); | |
82 | } | |
83 | if (trans->transid != root->fs_info->generation) { | |
84 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
85 | root->fs_info->generation); | |
86 | WARN_ON(1); | |
87 | } | |
7f5c1516 CM |
88 | if (btrfs_header_generation(btrfs_buffer_header(buf)) == |
89 | trans->transid) { | |
02217ed2 CM |
90 | *cow_ret = buf; |
91 | return 0; | |
92 | } | |
31f3c99b | 93 | cow = btrfs_alloc_free_block(trans, root, buf->b_blocknr); |
54aa1f4d CM |
94 | if (IS_ERR(cow)) |
95 | return PTR_ERR(cow); | |
e20d96d6 | 96 | cow_node = btrfs_buffer_node(cow); |
2c90e5d6 CM |
97 | if (buf->b_size != root->blocksize || cow->b_size != root->blocksize) |
98 | WARN_ON(1); | |
e20d96d6 | 99 | memcpy(cow_node, btrfs_buffer_node(buf), root->blocksize); |
7eccb903 | 100 | btrfs_set_header_blocknr(&cow_node->header, bh_blocknr(cow)); |
7f5c1516 | 101 | btrfs_set_header_generation(&cow_node->header, trans->transid); |
4d775673 | 102 | btrfs_set_header_owner(&cow_node->header, root->root_key.objectid); |
54aa1f4d CM |
103 | ret = btrfs_inc_ref(trans, root, buf); |
104 | if (ret) | |
105 | return ret; | |
02217ed2 CM |
106 | if (buf == root->node) { |
107 | root->node = cow; | |
e20d96d6 | 108 | get_bh(cow); |
2c90e5d6 | 109 | if (buf != root->commit_root) { |
7eccb903 | 110 | btrfs_free_extent(trans, root, bh_blocknr(buf), 1, 1); |
2c90e5d6 | 111 | } |
234b63a0 | 112 | btrfs_block_release(root, buf); |
02217ed2 | 113 | } else { |
e20d96d6 | 114 | btrfs_set_node_blockptr(btrfs_buffer_node(parent), parent_slot, |
7eccb903 | 115 | bh_blocknr(cow)); |
d6025579 | 116 | btrfs_mark_buffer_dirty(parent); |
7eccb903 | 117 | btrfs_free_extent(trans, root, bh_blocknr(buf), 1, 1); |
02217ed2 | 118 | } |
234b63a0 | 119 | btrfs_block_release(root, buf); |
ccd467d6 | 120 | btrfs_mark_buffer_dirty(cow); |
2c90e5d6 | 121 | *cow_ret = cow; |
02217ed2 CM |
122 | return 0; |
123 | } | |
124 | ||
74123bd7 CM |
125 | /* |
126 | * The leaf data grows from end-to-front in the node. | |
127 | * this returns the address of the start of the last item, | |
128 | * which is the stop of the leaf data stack | |
129 | */ | |
123abc88 CM |
130 | static inline unsigned int leaf_data_end(struct btrfs_root *root, |
131 | struct btrfs_leaf *leaf) | |
be0e5c09 | 132 | { |
7518a238 | 133 | u32 nr = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 134 | if (nr == 0) |
123abc88 | 135 | return BTRFS_LEAF_DATA_SIZE(root); |
0783fcfc | 136 | return btrfs_item_offset(leaf->items + nr - 1); |
be0e5c09 CM |
137 | } |
138 | ||
74123bd7 CM |
139 | /* |
140 | * compare two keys in a memcmp fashion | |
141 | */ | |
9aca1d51 | 142 | static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2) |
be0e5c09 | 143 | { |
e2fa7227 CM |
144 | struct btrfs_key k1; |
145 | ||
146 | btrfs_disk_key_to_cpu(&k1, disk); | |
147 | ||
148 | if (k1.objectid > k2->objectid) | |
be0e5c09 | 149 | return 1; |
e2fa7227 | 150 | if (k1.objectid < k2->objectid) |
be0e5c09 | 151 | return -1; |
f254e52c CM |
152 | if (k1.flags > k2->flags) |
153 | return 1; | |
154 | if (k1.flags < k2->flags) | |
155 | return -1; | |
70b2befd CM |
156 | if (k1.offset > k2->offset) |
157 | return 1; | |
158 | if (k1.offset < k2->offset) | |
159 | return -1; | |
be0e5c09 CM |
160 | return 0; |
161 | } | |
74123bd7 | 162 | |
123abc88 CM |
163 | static int check_node(struct btrfs_root *root, struct btrfs_path *path, |
164 | int level) | |
aa5d6bed | 165 | { |
234b63a0 | 166 | struct btrfs_node *parent = NULL; |
e20d96d6 | 167 | struct btrfs_node *node = btrfs_buffer_node(path->nodes[level]); |
aa5d6bed | 168 | int parent_slot; |
8d7be552 CM |
169 | int slot; |
170 | struct btrfs_key cpukey; | |
7518a238 | 171 | u32 nritems = btrfs_header_nritems(&node->header); |
aa5d6bed CM |
172 | |
173 | if (path->nodes[level + 1]) | |
e20d96d6 | 174 | parent = btrfs_buffer_node(path->nodes[level + 1]); |
a1f39630 | 175 | |
8d7be552 | 176 | slot = path->slots[level]; |
7518a238 CM |
177 | BUG_ON(nritems == 0); |
178 | if (parent) { | |
e2fa7227 | 179 | struct btrfs_disk_key *parent_key; |
a1f39630 A |
180 | |
181 | parent_slot = path->slots[level + 1]; | |
123abc88 CM |
182 | parent_key = &parent->ptrs[parent_slot].key; |
183 | BUG_ON(memcmp(parent_key, &node->ptrs[0].key, | |
e2fa7227 | 184 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 185 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
7518a238 | 186 | btrfs_header_blocknr(&node->header)); |
aa5d6bed | 187 | } |
123abc88 | 188 | BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root)); |
8d7be552 CM |
189 | if (slot != 0) { |
190 | btrfs_disk_key_to_cpu(&cpukey, &node->ptrs[slot - 1].key); | |
191 | BUG_ON(comp_keys(&node->ptrs[slot].key, &cpukey) <= 0); | |
192 | } | |
193 | if (slot < nritems - 1) { | |
194 | btrfs_disk_key_to_cpu(&cpukey, &node->ptrs[slot + 1].key); | |
195 | BUG_ON(comp_keys(&node->ptrs[slot].key, &cpukey) >= 0); | |
aa5d6bed CM |
196 | } |
197 | return 0; | |
198 | } | |
199 | ||
123abc88 CM |
200 | static int check_leaf(struct btrfs_root *root, struct btrfs_path *path, |
201 | int level) | |
aa5d6bed | 202 | { |
e20d96d6 | 203 | struct btrfs_leaf *leaf = btrfs_buffer_leaf(path->nodes[level]); |
234b63a0 | 204 | struct btrfs_node *parent = NULL; |
aa5d6bed | 205 | int parent_slot; |
8d7be552 CM |
206 | int slot = path->slots[0]; |
207 | struct btrfs_key cpukey; | |
208 | ||
7518a238 | 209 | u32 nritems = btrfs_header_nritems(&leaf->header); |
aa5d6bed CM |
210 | |
211 | if (path->nodes[level + 1]) | |
e20d96d6 | 212 | parent = btrfs_buffer_node(path->nodes[level + 1]); |
a1f39630 | 213 | |
123abc88 | 214 | BUG_ON(btrfs_leaf_free_space(root, leaf) < 0); |
7518a238 CM |
215 | |
216 | if (nritems == 0) | |
217 | return 0; | |
218 | ||
219 | if (parent) { | |
e2fa7227 | 220 | struct btrfs_disk_key *parent_key; |
a1f39630 A |
221 | |
222 | parent_slot = path->slots[level + 1]; | |
123abc88 | 223 | parent_key = &parent->ptrs[parent_slot].key; |
aa5d6bed | 224 | BUG_ON(memcmp(parent_key, &leaf->items[0].key, |
e2fa7227 | 225 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 226 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
7518a238 | 227 | btrfs_header_blocknr(&leaf->header)); |
aa5d6bed | 228 | } |
8d7be552 CM |
229 | if (slot != 0) { |
230 | btrfs_disk_key_to_cpu(&cpukey, &leaf->items[slot - 1].key); | |
231 | BUG_ON(comp_keys(&leaf->items[slot].key, &cpukey) <= 0); | |
232 | BUG_ON(btrfs_item_offset(leaf->items + slot - 1) != | |
233 | btrfs_item_end(leaf->items + slot)); | |
234 | } | |
235 | if (slot < nritems - 1) { | |
236 | btrfs_disk_key_to_cpu(&cpukey, &leaf->items[slot + 1].key); | |
237 | BUG_ON(comp_keys(&leaf->items[slot].key, &cpukey) >= 0); | |
238 | BUG_ON(btrfs_item_offset(leaf->items + slot) != | |
239 | btrfs_item_end(leaf->items + slot + 1)); | |
aa5d6bed | 240 | } |
8d7be552 CM |
241 | BUG_ON(btrfs_item_offset(leaf->items) + |
242 | btrfs_item_size(leaf->items) != BTRFS_LEAF_DATA_SIZE(root)); | |
aa5d6bed CM |
243 | return 0; |
244 | } | |
245 | ||
123abc88 CM |
246 | static int check_block(struct btrfs_root *root, struct btrfs_path *path, |
247 | int level) | |
aa5d6bed | 248 | { |
3eb0314d CM |
249 | struct btrfs_node *node = btrfs_buffer_node(path->nodes[level]); |
250 | if (memcmp(node->header.fsid, root->fs_info->disk_super->fsid, | |
251 | sizeof(node->header.fsid))) | |
252 | BUG(); | |
aa5d6bed | 253 | if (level == 0) |
123abc88 CM |
254 | return check_leaf(root, path, level); |
255 | return check_node(root, path, level); | |
aa5d6bed CM |
256 | } |
257 | ||
74123bd7 CM |
258 | /* |
259 | * search for key in the array p. items p are item_size apart | |
260 | * and there are 'max' items in p | |
261 | * the slot in the array is returned via slot, and it points to | |
262 | * the place where you would insert key if it is not found in | |
263 | * the array. | |
264 | * | |
265 | * slot may point to max if the key is bigger than all of the keys | |
266 | */ | |
9aca1d51 | 267 | static int generic_bin_search(char *p, int item_size, struct btrfs_key *key, |
be0e5c09 CM |
268 | int max, int *slot) |
269 | { | |
270 | int low = 0; | |
271 | int high = max; | |
272 | int mid; | |
273 | int ret; | |
e2fa7227 | 274 | struct btrfs_disk_key *tmp; |
be0e5c09 CM |
275 | |
276 | while(low < high) { | |
277 | mid = (low + high) / 2; | |
e2fa7227 | 278 | tmp = (struct btrfs_disk_key *)(p + mid * item_size); |
be0e5c09 CM |
279 | ret = comp_keys(tmp, key); |
280 | ||
281 | if (ret < 0) | |
282 | low = mid + 1; | |
283 | else if (ret > 0) | |
284 | high = mid; | |
285 | else { | |
286 | *slot = mid; | |
287 | return 0; | |
288 | } | |
289 | } | |
290 | *slot = low; | |
291 | return 1; | |
292 | } | |
293 | ||
97571fd0 CM |
294 | /* |
295 | * simple bin_search frontend that does the right thing for | |
296 | * leaves vs nodes | |
297 | */ | |
9aca1d51 | 298 | static int bin_search(struct btrfs_node *c, struct btrfs_key *key, int *slot) |
be0e5c09 | 299 | { |
7518a238 | 300 | if (btrfs_is_leaf(c)) { |
234b63a0 | 301 | struct btrfs_leaf *l = (struct btrfs_leaf *)c; |
0783fcfc CM |
302 | return generic_bin_search((void *)l->items, |
303 | sizeof(struct btrfs_item), | |
7518a238 CM |
304 | key, btrfs_header_nritems(&c->header), |
305 | slot); | |
be0e5c09 | 306 | } else { |
123abc88 CM |
307 | return generic_bin_search((void *)c->ptrs, |
308 | sizeof(struct btrfs_key_ptr), | |
7518a238 CM |
309 | key, btrfs_header_nritems(&c->header), |
310 | slot); | |
be0e5c09 CM |
311 | } |
312 | return -1; | |
313 | } | |
314 | ||
e20d96d6 CM |
315 | static struct buffer_head *read_node_slot(struct btrfs_root *root, |
316 | struct buffer_head *parent_buf, | |
bb803951 CM |
317 | int slot) |
318 | { | |
e20d96d6 | 319 | struct btrfs_node *node = btrfs_buffer_node(parent_buf); |
bb803951 CM |
320 | if (slot < 0) |
321 | return NULL; | |
7518a238 | 322 | if (slot >= btrfs_header_nritems(&node->header)) |
bb803951 | 323 | return NULL; |
1d4f8a0c | 324 | return read_tree_block(root, btrfs_node_blockptr(node, slot)); |
bb803951 CM |
325 | } |
326 | ||
e089f05c CM |
327 | static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root |
328 | *root, struct btrfs_path *path, int level) | |
bb803951 | 329 | { |
e20d96d6 CM |
330 | struct buffer_head *right_buf; |
331 | struct buffer_head *mid_buf; | |
332 | struct buffer_head *left_buf; | |
333 | struct buffer_head *parent_buf = NULL; | |
234b63a0 CM |
334 | struct btrfs_node *right = NULL; |
335 | struct btrfs_node *mid; | |
336 | struct btrfs_node *left = NULL; | |
337 | struct btrfs_node *parent = NULL; | |
bb803951 CM |
338 | int ret = 0; |
339 | int wret; | |
340 | int pslot; | |
bb803951 | 341 | int orig_slot = path->slots[level]; |
54aa1f4d | 342 | int err_on_enospc = 0; |
79f95c82 | 343 | u64 orig_ptr; |
bb803951 CM |
344 | |
345 | if (level == 0) | |
346 | return 0; | |
347 | ||
348 | mid_buf = path->nodes[level]; | |
e20d96d6 | 349 | mid = btrfs_buffer_node(mid_buf); |
1d4f8a0c | 350 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
79f95c82 | 351 | |
234b63a0 | 352 | if (level < BTRFS_MAX_LEVEL - 1) |
bb803951 CM |
353 | parent_buf = path->nodes[level + 1]; |
354 | pslot = path->slots[level + 1]; | |
355 | ||
40689478 CM |
356 | /* |
357 | * deal with the case where there is only one pointer in the root | |
358 | * by promoting the node below to a root | |
359 | */ | |
bb803951 | 360 | if (!parent_buf) { |
e20d96d6 | 361 | struct buffer_head *child; |
7eccb903 | 362 | u64 blocknr = bh_blocknr(mid_buf); |
bb803951 | 363 | |
7518a238 | 364 | if (btrfs_header_nritems(&mid->header) != 1) |
bb803951 CM |
365 | return 0; |
366 | ||
367 | /* promote the child to a root */ | |
368 | child = read_node_slot(root, mid_buf, 0); | |
369 | BUG_ON(!child); | |
370 | root->node = child; | |
371 | path->nodes[level] = NULL; | |
d6025579 CM |
372 | clean_tree_block(trans, root, mid_buf); |
373 | wait_on_buffer(mid_buf); | |
bb803951 | 374 | /* once for the path */ |
234b63a0 | 375 | btrfs_block_release(root, mid_buf); |
bb803951 | 376 | /* once for the root ptr */ |
234b63a0 | 377 | btrfs_block_release(root, mid_buf); |
e089f05c | 378 | return btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 | 379 | } |
e20d96d6 | 380 | parent = btrfs_buffer_node(parent_buf); |
bb803951 | 381 | |
123abc88 CM |
382 | if (btrfs_header_nritems(&mid->header) > |
383 | BTRFS_NODEPTRS_PER_BLOCK(root) / 4) | |
bb803951 CM |
384 | return 0; |
385 | ||
54aa1f4d CM |
386 | if (btrfs_header_nritems(&mid->header) < 2) |
387 | err_on_enospc = 1; | |
388 | ||
bb803951 CM |
389 | left_buf = read_node_slot(root, parent_buf, pslot - 1); |
390 | right_buf = read_node_slot(root, parent_buf, pslot + 1); | |
79f95c82 CM |
391 | |
392 | /* first, try to make some room in the middle buffer */ | |
bb803951 | 393 | if (left_buf) { |
54aa1f4d CM |
394 | wret = btrfs_cow_block(trans, root, left_buf, |
395 | parent_buf, pslot - 1, &left_buf); | |
396 | if (wret) { | |
397 | ret = wret; | |
398 | goto enospc; | |
399 | } | |
e20d96d6 | 400 | left = btrfs_buffer_node(left_buf); |
7518a238 | 401 | orig_slot += btrfs_header_nritems(&left->header); |
e089f05c | 402 | wret = push_node_left(trans, root, left_buf, mid_buf); |
79f95c82 CM |
403 | if (wret < 0) |
404 | ret = wret; | |
54aa1f4d CM |
405 | if (btrfs_header_nritems(&mid->header) < 2) |
406 | err_on_enospc = 1; | |
bb803951 | 407 | } |
79f95c82 CM |
408 | |
409 | /* | |
410 | * then try to empty the right most buffer into the middle | |
411 | */ | |
bb803951 | 412 | if (right_buf) { |
54aa1f4d CM |
413 | wret = btrfs_cow_block(trans, root, right_buf, |
414 | parent_buf, pslot + 1, &right_buf); | |
415 | if (wret) { | |
416 | ret = wret; | |
417 | goto enospc; | |
418 | } | |
419 | ||
e20d96d6 | 420 | right = btrfs_buffer_node(right_buf); |
e089f05c | 421 | wret = push_node_left(trans, root, mid_buf, right_buf); |
54aa1f4d | 422 | if (wret < 0 && wret != -ENOSPC) |
79f95c82 | 423 | ret = wret; |
7518a238 | 424 | if (btrfs_header_nritems(&right->header) == 0) { |
7eccb903 | 425 | u64 blocknr = bh_blocknr(right_buf); |
e089f05c | 426 | clean_tree_block(trans, root, right_buf); |
d6025579 CM |
427 | wait_on_buffer(right_buf); |
428 | btrfs_block_release(root, right_buf); | |
bb803951 CM |
429 | right_buf = NULL; |
430 | right = NULL; | |
e089f05c CM |
431 | wret = del_ptr(trans, root, path, level + 1, pslot + |
432 | 1); | |
bb803951 CM |
433 | if (wret) |
434 | ret = wret; | |
e089f05c | 435 | wret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 CM |
436 | if (wret) |
437 | ret = wret; | |
438 | } else { | |
d6025579 CM |
439 | btrfs_memcpy(root, parent, |
440 | &parent->ptrs[pslot + 1].key, | |
441 | &right->ptrs[0].key, | |
442 | sizeof(struct btrfs_disk_key)); | |
443 | btrfs_mark_buffer_dirty(parent_buf); | |
bb803951 CM |
444 | } |
445 | } | |
7518a238 | 446 | if (btrfs_header_nritems(&mid->header) == 1) { |
79f95c82 CM |
447 | /* |
448 | * we're not allowed to leave a node with one item in the | |
449 | * tree during a delete. A deletion from lower in the tree | |
450 | * could try to delete the only pointer in this node. | |
451 | * So, pull some keys from the left. | |
452 | * There has to be a left pointer at this point because | |
453 | * otherwise we would have pulled some pointers from the | |
454 | * right | |
455 | */ | |
456 | BUG_ON(!left_buf); | |
e089f05c | 457 | wret = balance_node_right(trans, root, mid_buf, left_buf); |
54aa1f4d | 458 | if (wret < 0) { |
79f95c82 | 459 | ret = wret; |
54aa1f4d CM |
460 | goto enospc; |
461 | } | |
79f95c82 CM |
462 | BUG_ON(wret == 1); |
463 | } | |
7518a238 | 464 | if (btrfs_header_nritems(&mid->header) == 0) { |
79f95c82 | 465 | /* we've managed to empty the middle node, drop it */ |
7eccb903 | 466 | u64 blocknr = bh_blocknr(mid_buf); |
e089f05c | 467 | clean_tree_block(trans, root, mid_buf); |
d6025579 CM |
468 | wait_on_buffer(mid_buf); |
469 | btrfs_block_release(root, mid_buf); | |
bb803951 CM |
470 | mid_buf = NULL; |
471 | mid = NULL; | |
e089f05c | 472 | wret = del_ptr(trans, root, path, level + 1, pslot); |
bb803951 CM |
473 | if (wret) |
474 | ret = wret; | |
e089f05c | 475 | wret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 CM |
476 | if (wret) |
477 | ret = wret; | |
79f95c82 CM |
478 | } else { |
479 | /* update the parent key to reflect our changes */ | |
d6025579 CM |
480 | btrfs_memcpy(root, parent, |
481 | &parent->ptrs[pslot].key, &mid->ptrs[0].key, | |
482 | sizeof(struct btrfs_disk_key)); | |
483 | btrfs_mark_buffer_dirty(parent_buf); | |
79f95c82 | 484 | } |
bb803951 | 485 | |
79f95c82 | 486 | /* update the path */ |
bb803951 | 487 | if (left_buf) { |
7518a238 | 488 | if (btrfs_header_nritems(&left->header) > orig_slot) { |
e20d96d6 | 489 | get_bh(left_buf); |
bb803951 CM |
490 | path->nodes[level] = left_buf; |
491 | path->slots[level + 1] -= 1; | |
492 | path->slots[level] = orig_slot; | |
493 | if (mid_buf) | |
234b63a0 | 494 | btrfs_block_release(root, mid_buf); |
bb803951 | 495 | } else { |
7518a238 | 496 | orig_slot -= btrfs_header_nritems(&left->header); |
bb803951 CM |
497 | path->slots[level] = orig_slot; |
498 | } | |
499 | } | |
79f95c82 | 500 | /* double check we haven't messed things up */ |
123abc88 | 501 | check_block(root, path, level); |
e20d96d6 CM |
502 | if (orig_ptr != |
503 | btrfs_node_blockptr(btrfs_buffer_node(path->nodes[level]), | |
504 | path->slots[level])) | |
79f95c82 | 505 | BUG(); |
54aa1f4d | 506 | enospc: |
bb803951 | 507 | if (right_buf) |
234b63a0 | 508 | btrfs_block_release(root, right_buf); |
bb803951 | 509 | if (left_buf) |
234b63a0 | 510 | btrfs_block_release(root, left_buf); |
bb803951 CM |
511 | return ret; |
512 | } | |
513 | ||
e66f709b CM |
514 | /* returns zero if the push worked, non-zero otherwise */ |
515 | static int push_nodes_for_insert(struct btrfs_trans_handle *trans, | |
516 | struct btrfs_root *root, | |
517 | struct btrfs_path *path, int level) | |
518 | { | |
519 | struct buffer_head *right_buf; | |
520 | struct buffer_head *mid_buf; | |
521 | struct buffer_head *left_buf; | |
522 | struct buffer_head *parent_buf = NULL; | |
523 | struct btrfs_node *right = NULL; | |
524 | struct btrfs_node *mid; | |
525 | struct btrfs_node *left = NULL; | |
526 | struct btrfs_node *parent = NULL; | |
527 | int ret = 0; | |
528 | int wret; | |
529 | int pslot; | |
530 | int orig_slot = path->slots[level]; | |
531 | u64 orig_ptr; | |
532 | ||
533 | if (level == 0) | |
534 | return 1; | |
535 | ||
536 | mid_buf = path->nodes[level]; | |
537 | mid = btrfs_buffer_node(mid_buf); | |
538 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); | |
539 | ||
540 | if (level < BTRFS_MAX_LEVEL - 1) | |
541 | parent_buf = path->nodes[level + 1]; | |
542 | pslot = path->slots[level + 1]; | |
543 | ||
544 | if (!parent_buf) | |
545 | return 1; | |
546 | parent = btrfs_buffer_node(parent_buf); | |
547 | ||
548 | left_buf = read_node_slot(root, parent_buf, pslot - 1); | |
549 | ||
550 | /* first, try to make some room in the middle buffer */ | |
551 | if (left_buf) { | |
552 | u32 left_nr; | |
e66f709b CM |
553 | left = btrfs_buffer_node(left_buf); |
554 | left_nr = btrfs_header_nritems(&left->header); | |
33ade1f8 CM |
555 | if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
556 | wret = 1; | |
557 | } else { | |
54aa1f4d CM |
558 | ret = btrfs_cow_block(trans, root, left_buf, parent_buf, |
559 | pslot - 1, &left_buf); | |
560 | if (ret) | |
561 | wret = 1; | |
562 | else { | |
563 | left = btrfs_buffer_node(left_buf); | |
564 | wret = push_node_left(trans, root, | |
565 | left_buf, mid_buf); | |
566 | } | |
33ade1f8 | 567 | } |
e66f709b CM |
568 | if (wret < 0) |
569 | ret = wret; | |
570 | if (wret == 0) { | |
571 | orig_slot += left_nr; | |
572 | btrfs_memcpy(root, parent, | |
573 | &parent->ptrs[pslot].key, | |
574 | &mid->ptrs[0].key, | |
575 | sizeof(struct btrfs_disk_key)); | |
576 | btrfs_mark_buffer_dirty(parent_buf); | |
577 | if (btrfs_header_nritems(&left->header) > orig_slot) { | |
578 | path->nodes[level] = left_buf; | |
579 | path->slots[level + 1] -= 1; | |
580 | path->slots[level] = orig_slot; | |
581 | btrfs_block_release(root, mid_buf); | |
582 | } else { | |
583 | orig_slot -= | |
584 | btrfs_header_nritems(&left->header); | |
585 | path->slots[level] = orig_slot; | |
586 | btrfs_block_release(root, left_buf); | |
587 | } | |
588 | check_node(root, path, level); | |
589 | return 0; | |
590 | } | |
591 | btrfs_block_release(root, left_buf); | |
592 | } | |
593 | right_buf = read_node_slot(root, parent_buf, pslot + 1); | |
594 | ||
595 | /* | |
596 | * then try to empty the right most buffer into the middle | |
597 | */ | |
598 | if (right_buf) { | |
33ade1f8 | 599 | u32 right_nr; |
e66f709b | 600 | right = btrfs_buffer_node(right_buf); |
33ade1f8 CM |
601 | right_nr = btrfs_header_nritems(&right->header); |
602 | if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { | |
603 | wret = 1; | |
604 | } else { | |
54aa1f4d CM |
605 | ret = btrfs_cow_block(trans, root, right_buf, |
606 | parent_buf, pslot + 1, | |
607 | &right_buf); | |
608 | if (ret) | |
609 | wret = 1; | |
610 | else { | |
611 | right = btrfs_buffer_node(right_buf); | |
612 | wret = balance_node_right(trans, root, | |
613 | right_buf, mid_buf); | |
614 | } | |
33ade1f8 | 615 | } |
e66f709b CM |
616 | if (wret < 0) |
617 | ret = wret; | |
618 | if (wret == 0) { | |
619 | btrfs_memcpy(root, parent, | |
620 | &parent->ptrs[pslot + 1].key, | |
621 | &right->ptrs[0].key, | |
622 | sizeof(struct btrfs_disk_key)); | |
623 | btrfs_mark_buffer_dirty(parent_buf); | |
624 | if (btrfs_header_nritems(&mid->header) <= orig_slot) { | |
625 | path->nodes[level] = right_buf; | |
626 | path->slots[level + 1] += 1; | |
627 | path->slots[level] = orig_slot - | |
628 | btrfs_header_nritems(&mid->header); | |
629 | btrfs_block_release(root, mid_buf); | |
630 | } else { | |
631 | btrfs_block_release(root, right_buf); | |
632 | } | |
633 | check_node(root, path, level); | |
634 | return 0; | |
635 | } | |
636 | btrfs_block_release(root, right_buf); | |
637 | } | |
638 | check_node(root, path, level); | |
639 | return 1; | |
640 | } | |
641 | ||
74123bd7 CM |
642 | /* |
643 | * look for key in the tree. path is filled in with nodes along the way | |
644 | * if key is found, we return zero and you can find the item in the leaf | |
645 | * level of the path (level 0) | |
646 | * | |
647 | * If the key isn't found, the path points to the slot where it should | |
aa5d6bed CM |
648 | * be inserted, and 1 is returned. If there are other errors during the |
649 | * search a negative error number is returned. | |
97571fd0 CM |
650 | * |
651 | * if ins_len > 0, nodes and leaves will be split as we walk down the | |
652 | * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if | |
653 | * possible) | |
74123bd7 | 654 | */ |
e089f05c CM |
655 | int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root |
656 | *root, struct btrfs_key *key, struct btrfs_path *p, int | |
657 | ins_len, int cow) | |
be0e5c09 | 658 | { |
e20d96d6 CM |
659 | struct buffer_head *b; |
660 | struct buffer_head *cow_buf; | |
234b63a0 | 661 | struct btrfs_node *c; |
9f3a7427 | 662 | struct btrfs_root_item *root_item = &root->root_item; |
be0e5c09 CM |
663 | int slot; |
664 | int ret; | |
665 | int level; | |
9f3a7427 CM |
666 | u8 lowest_level = 0; |
667 | ||
668 | if (btrfs_root_refs(root_item) == 0 && root->ref_cows) { | |
669 | lowest_level = root_item->drop_level; | |
670 | WARN_ON(ins_len || cow); | |
671 | } | |
5c680ed6 | 672 | |
22b0ebda CM |
673 | WARN_ON(p->nodes[0] != NULL); |
674 | WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex)); | |
bb803951 CM |
675 | again: |
676 | b = root->node; | |
e20d96d6 | 677 | get_bh(b); |
eb60ceac | 678 | while (b) { |
e20d96d6 CM |
679 | c = btrfs_buffer_node(b); |
680 | level = btrfs_header_level(&c->header); | |
02217ed2 CM |
681 | if (cow) { |
682 | int wret; | |
e20d96d6 CM |
683 | wret = btrfs_cow_block(trans, root, b, |
684 | p->nodes[level + 1], | |
685 | p->slots[level + 1], | |
e089f05c | 686 | &cow_buf); |
54aa1f4d CM |
687 | if (wret) { |
688 | btrfs_block_release(root, cow_buf); | |
689 | return wret; | |
690 | } | |
02217ed2 | 691 | b = cow_buf; |
2c90e5d6 | 692 | c = btrfs_buffer_node(b); |
02217ed2 CM |
693 | } |
694 | BUG_ON(!cow && ins_len); | |
2c90e5d6 CM |
695 | if (level != btrfs_header_level(&c->header)) |
696 | WARN_ON(1); | |
697 | level = btrfs_header_level(&c->header); | |
eb60ceac | 698 | p->nodes[level] = b; |
123abc88 | 699 | ret = check_block(root, p, level); |
aa5d6bed CM |
700 | if (ret) |
701 | return -1; | |
be0e5c09 | 702 | ret = bin_search(c, key, &slot); |
7518a238 | 703 | if (!btrfs_is_leaf(c)) { |
be0e5c09 CM |
704 | if (ret && slot > 0) |
705 | slot -= 1; | |
706 | p->slots[level] = slot; | |
d4dbff95 CM |
707 | if (ins_len > 0 && btrfs_header_nritems(&c->header) >= |
708 | BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { | |
e089f05c | 709 | int sret = split_node(trans, root, p, level); |
5c680ed6 CM |
710 | BUG_ON(sret > 0); |
711 | if (sret) | |
712 | return sret; | |
713 | b = p->nodes[level]; | |
e20d96d6 | 714 | c = btrfs_buffer_node(b); |
5c680ed6 | 715 | slot = p->slots[level]; |
bb803951 | 716 | } else if (ins_len < 0) { |
e089f05c CM |
717 | int sret = balance_level(trans, root, p, |
718 | level); | |
bb803951 CM |
719 | if (sret) |
720 | return sret; | |
721 | b = p->nodes[level]; | |
722 | if (!b) | |
723 | goto again; | |
e20d96d6 | 724 | c = btrfs_buffer_node(b); |
bb803951 | 725 | slot = p->slots[level]; |
7518a238 | 726 | BUG_ON(btrfs_header_nritems(&c->header) == 1); |
5c680ed6 | 727 | } |
9f3a7427 CM |
728 | /* this is only true while dropping a snapshot */ |
729 | if (level == lowest_level) | |
730 | break; | |
1d4f8a0c | 731 | b = read_tree_block(root, btrfs_node_blockptr(c, slot)); |
be0e5c09 | 732 | } else { |
234b63a0 | 733 | struct btrfs_leaf *l = (struct btrfs_leaf *)c; |
be0e5c09 | 734 | p->slots[level] = slot; |
123abc88 | 735 | if (ins_len > 0 && btrfs_leaf_free_space(root, l) < |
0783fcfc | 736 | sizeof(struct btrfs_item) + ins_len) { |
d4dbff95 CM |
737 | int sret = split_leaf(trans, root, key, |
738 | p, ins_len); | |
5c680ed6 CM |
739 | BUG_ON(sret > 0); |
740 | if (sret) | |
741 | return sret; | |
742 | } | |
be0e5c09 CM |
743 | return ret; |
744 | } | |
745 | } | |
aa5d6bed | 746 | return 1; |
be0e5c09 CM |
747 | } |
748 | ||
74123bd7 CM |
749 | /* |
750 | * adjust the pointers going up the tree, starting at level | |
751 | * making sure the right key of each node is points to 'key'. | |
752 | * This is used after shifting pointers to the left, so it stops | |
753 | * fixing up pointers when a given leaf/node is not in slot 0 of the | |
754 | * higher levels | |
aa5d6bed CM |
755 | * |
756 | * If this fails to write a tree block, it returns -1, but continues | |
757 | * fixing up the blocks in ram so the tree is consistent. | |
74123bd7 | 758 | */ |
e089f05c CM |
759 | static int fixup_low_keys(struct btrfs_trans_handle *trans, struct btrfs_root |
760 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
761 | *key, int level) | |
be0e5c09 CM |
762 | { |
763 | int i; | |
aa5d6bed | 764 | int ret = 0; |
234b63a0 CM |
765 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
766 | struct btrfs_node *t; | |
be0e5c09 | 767 | int tslot = path->slots[i]; |
eb60ceac | 768 | if (!path->nodes[i]) |
be0e5c09 | 769 | break; |
e20d96d6 | 770 | t = btrfs_buffer_node(path->nodes[i]); |
d6025579 CM |
771 | btrfs_memcpy(root, t, &t->ptrs[tslot].key, key, sizeof(*key)); |
772 | btrfs_mark_buffer_dirty(path->nodes[i]); | |
be0e5c09 CM |
773 | if (tslot != 0) |
774 | break; | |
775 | } | |
aa5d6bed | 776 | return ret; |
be0e5c09 CM |
777 | } |
778 | ||
74123bd7 CM |
779 | /* |
780 | * try to push data from one node into the next node left in the | |
79f95c82 | 781 | * tree. |
aa5d6bed CM |
782 | * |
783 | * returns 0 if some ptrs were pushed left, < 0 if there was some horrible | |
784 | * error, and > 0 if there was no room in the left hand block. | |
74123bd7 | 785 | */ |
e089f05c | 786 | static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root |
e20d96d6 CM |
787 | *root, struct buffer_head *dst_buf, struct |
788 | buffer_head *src_buf) | |
be0e5c09 | 789 | { |
e20d96d6 CM |
790 | struct btrfs_node *src = btrfs_buffer_node(src_buf); |
791 | struct btrfs_node *dst = btrfs_buffer_node(dst_buf); | |
be0e5c09 | 792 | int push_items = 0; |
bb803951 CM |
793 | int src_nritems; |
794 | int dst_nritems; | |
aa5d6bed | 795 | int ret = 0; |
be0e5c09 | 796 | |
7518a238 CM |
797 | src_nritems = btrfs_header_nritems(&src->header); |
798 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 799 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
54aa1f4d | 800 | |
eb60ceac | 801 | if (push_items <= 0) { |
be0e5c09 | 802 | return 1; |
eb60ceac | 803 | } |
be0e5c09 | 804 | |
bb803951 | 805 | if (src_nritems < push_items) |
79f95c82 CM |
806 | push_items = src_nritems; |
807 | ||
d6025579 CM |
808 | btrfs_memcpy(root, dst, dst->ptrs + dst_nritems, src->ptrs, |
809 | push_items * sizeof(struct btrfs_key_ptr)); | |
bb803951 | 810 | if (push_items < src_nritems) { |
d6025579 | 811 | btrfs_memmove(root, src, src->ptrs, src->ptrs + push_items, |
e2fa7227 | 812 | (src_nritems - push_items) * |
123abc88 | 813 | sizeof(struct btrfs_key_ptr)); |
bb803951 | 814 | } |
7518a238 CM |
815 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
816 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
d6025579 CM |
817 | btrfs_mark_buffer_dirty(src_buf); |
818 | btrfs_mark_buffer_dirty(dst_buf); | |
79f95c82 CM |
819 | return ret; |
820 | } | |
821 | ||
822 | /* | |
823 | * try to push data from one node into the next node right in the | |
824 | * tree. | |
825 | * | |
826 | * returns 0 if some ptrs were pushed, < 0 if there was some horrible | |
827 | * error, and > 0 if there was no room in the right hand block. | |
828 | * | |
829 | * this will only push up to 1/2 the contents of the left node over | |
830 | */ | |
e089f05c | 831 | static int balance_node_right(struct btrfs_trans_handle *trans, struct |
e20d96d6 CM |
832 | btrfs_root *root, struct buffer_head *dst_buf, |
833 | struct buffer_head *src_buf) | |
79f95c82 | 834 | { |
e20d96d6 CM |
835 | struct btrfs_node *src = btrfs_buffer_node(src_buf); |
836 | struct btrfs_node *dst = btrfs_buffer_node(dst_buf); | |
79f95c82 CM |
837 | int push_items = 0; |
838 | int max_push; | |
839 | int src_nritems; | |
840 | int dst_nritems; | |
841 | int ret = 0; | |
79f95c82 | 842 | |
7518a238 CM |
843 | src_nritems = btrfs_header_nritems(&src->header); |
844 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 845 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
79f95c82 CM |
846 | if (push_items <= 0) { |
847 | return 1; | |
848 | } | |
849 | ||
850 | max_push = src_nritems / 2 + 1; | |
851 | /* don't try to empty the node */ | |
852 | if (max_push > src_nritems) | |
853 | return 1; | |
854 | if (max_push < push_items) | |
855 | push_items = max_push; | |
856 | ||
d6025579 CM |
857 | btrfs_memmove(root, dst, dst->ptrs + push_items, dst->ptrs, |
858 | dst_nritems * sizeof(struct btrfs_key_ptr)); | |
859 | ||
860 | btrfs_memcpy(root, dst, dst->ptrs, | |
861 | src->ptrs + src_nritems - push_items, | |
862 | push_items * sizeof(struct btrfs_key_ptr)); | |
79f95c82 | 863 | |
7518a238 CM |
864 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
865 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
79f95c82 | 866 | |
d6025579 CM |
867 | btrfs_mark_buffer_dirty(src_buf); |
868 | btrfs_mark_buffer_dirty(dst_buf); | |
aa5d6bed | 869 | return ret; |
be0e5c09 CM |
870 | } |
871 | ||
97571fd0 CM |
872 | /* |
873 | * helper function to insert a new root level in the tree. | |
874 | * A new node is allocated, and a single item is inserted to | |
875 | * point to the existing root | |
aa5d6bed CM |
876 | * |
877 | * returns zero on success or < 0 on failure. | |
97571fd0 | 878 | */ |
e089f05c CM |
879 | static int insert_new_root(struct btrfs_trans_handle *trans, struct btrfs_root |
880 | *root, struct btrfs_path *path, int level) | |
5c680ed6 | 881 | { |
e20d96d6 | 882 | struct buffer_head *t; |
234b63a0 CM |
883 | struct btrfs_node *lower; |
884 | struct btrfs_node *c; | |
e2fa7227 | 885 | struct btrfs_disk_key *lower_key; |
5c680ed6 CM |
886 | |
887 | BUG_ON(path->nodes[level]); | |
888 | BUG_ON(path->nodes[level-1] != root->node); | |
889 | ||
31f3c99b | 890 | t = btrfs_alloc_free_block(trans, root, root->node->b_blocknr); |
54aa1f4d CM |
891 | if (IS_ERR(t)) |
892 | return PTR_ERR(t); | |
e20d96d6 | 893 | c = btrfs_buffer_node(t); |
123abc88 | 894 | memset(c, 0, root->blocksize); |
7518a238 CM |
895 | btrfs_set_header_nritems(&c->header, 1); |
896 | btrfs_set_header_level(&c->header, level); | |
7eccb903 | 897 | btrfs_set_header_blocknr(&c->header, bh_blocknr(t)); |
7f5c1516 | 898 | btrfs_set_header_generation(&c->header, trans->transid); |
4d775673 | 899 | btrfs_set_header_owner(&c->header, root->root_key.objectid); |
e20d96d6 | 900 | lower = btrfs_buffer_node(path->nodes[level-1]); |
3eb0314d CM |
901 | memcpy(c->header.fsid, root->fs_info->disk_super->fsid, |
902 | sizeof(c->header.fsid)); | |
7518a238 | 903 | if (btrfs_is_leaf(lower)) |
234b63a0 | 904 | lower_key = &((struct btrfs_leaf *)lower)->items[0].key; |
5c680ed6 | 905 | else |
123abc88 | 906 | lower_key = &lower->ptrs[0].key; |
d6025579 CM |
907 | btrfs_memcpy(root, c, &c->ptrs[0].key, lower_key, |
908 | sizeof(struct btrfs_disk_key)); | |
7eccb903 | 909 | btrfs_set_node_blockptr(c, 0, bh_blocknr(path->nodes[level - 1])); |
d5719762 | 910 | |
d6025579 | 911 | btrfs_mark_buffer_dirty(t); |
d5719762 | 912 | |
5c680ed6 | 913 | /* the super has an extra ref to root->node */ |
234b63a0 | 914 | btrfs_block_release(root, root->node); |
5c680ed6 | 915 | root->node = t; |
e20d96d6 | 916 | get_bh(t); |
5c680ed6 CM |
917 | path->nodes[level] = t; |
918 | path->slots[level] = 0; | |
919 | return 0; | |
920 | } | |
921 | ||
74123bd7 CM |
922 | /* |
923 | * worker function to insert a single pointer in a node. | |
924 | * the node should have enough room for the pointer already | |
97571fd0 | 925 | * |
74123bd7 CM |
926 | * slot and level indicate where you want the key to go, and |
927 | * blocknr is the block the key points to. | |
aa5d6bed CM |
928 | * |
929 | * returns zero on success and < 0 on any error | |
74123bd7 | 930 | */ |
e089f05c CM |
931 | static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root |
932 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
933 | *key, u64 blocknr, int slot, int level) | |
74123bd7 | 934 | { |
234b63a0 | 935 | struct btrfs_node *lower; |
74123bd7 | 936 | int nritems; |
5c680ed6 CM |
937 | |
938 | BUG_ON(!path->nodes[level]); | |
e20d96d6 | 939 | lower = btrfs_buffer_node(path->nodes[level]); |
7518a238 | 940 | nritems = btrfs_header_nritems(&lower->header); |
74123bd7 CM |
941 | if (slot > nritems) |
942 | BUG(); | |
123abc88 | 943 | if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root)) |
74123bd7 CM |
944 | BUG(); |
945 | if (slot != nritems) { | |
d6025579 CM |
946 | btrfs_memmove(root, lower, lower->ptrs + slot + 1, |
947 | lower->ptrs + slot, | |
948 | (nritems - slot) * sizeof(struct btrfs_key_ptr)); | |
74123bd7 | 949 | } |
d6025579 CM |
950 | btrfs_memcpy(root, lower, &lower->ptrs[slot].key, |
951 | key, sizeof(struct btrfs_disk_key)); | |
1d4f8a0c | 952 | btrfs_set_node_blockptr(lower, slot, blocknr); |
7518a238 | 953 | btrfs_set_header_nritems(&lower->header, nritems + 1); |
d6025579 | 954 | btrfs_mark_buffer_dirty(path->nodes[level]); |
098f59c2 | 955 | check_node(root, path, level); |
74123bd7 CM |
956 | return 0; |
957 | } | |
958 | ||
97571fd0 CM |
959 | /* |
960 | * split the node at the specified level in path in two. | |
961 | * The path is corrected to point to the appropriate node after the split | |
962 | * | |
963 | * Before splitting this tries to make some room in the node by pushing | |
964 | * left and right, if either one works, it returns right away. | |
aa5d6bed CM |
965 | * |
966 | * returns 0 on success and < 0 on failure | |
97571fd0 | 967 | */ |
e089f05c CM |
968 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
969 | *root, struct btrfs_path *path, int level) | |
be0e5c09 | 970 | { |
e20d96d6 | 971 | struct buffer_head *t; |
234b63a0 | 972 | struct btrfs_node *c; |
e20d96d6 | 973 | struct buffer_head *split_buffer; |
234b63a0 | 974 | struct btrfs_node *split; |
be0e5c09 | 975 | int mid; |
5c680ed6 | 976 | int ret; |
aa5d6bed | 977 | int wret; |
7518a238 | 978 | u32 c_nritems; |
eb60ceac | 979 | |
5c680ed6 | 980 | t = path->nodes[level]; |
e20d96d6 | 981 | c = btrfs_buffer_node(t); |
5c680ed6 CM |
982 | if (t == root->node) { |
983 | /* trying to split the root, lets make a new one */ | |
e089f05c | 984 | ret = insert_new_root(trans, root, path, level + 1); |
5c680ed6 CM |
985 | if (ret) |
986 | return ret; | |
e66f709b CM |
987 | } else { |
988 | ret = push_nodes_for_insert(trans, root, path, level); | |
989 | t = path->nodes[level]; | |
990 | c = btrfs_buffer_node(t); | |
991 | if (!ret && | |
992 | btrfs_header_nritems(&c->header) < | |
993 | BTRFS_NODEPTRS_PER_BLOCK(root) - 1) | |
994 | return 0; | |
54aa1f4d CM |
995 | if (ret < 0) |
996 | return ret; | |
be0e5c09 | 997 | } |
e66f709b | 998 | |
7518a238 | 999 | c_nritems = btrfs_header_nritems(&c->header); |
31f3c99b | 1000 | split_buffer = btrfs_alloc_free_block(trans, root, t->b_blocknr); |
54aa1f4d CM |
1001 | if (IS_ERR(split_buffer)) |
1002 | return PTR_ERR(split_buffer); | |
1003 | ||
e20d96d6 | 1004 | split = btrfs_buffer_node(split_buffer); |
7518a238 | 1005 | btrfs_set_header_flags(&split->header, btrfs_header_flags(&c->header)); |
9a6f11ed | 1006 | btrfs_set_header_level(&split->header, btrfs_header_level(&c->header)); |
7eccb903 | 1007 | btrfs_set_header_blocknr(&split->header, bh_blocknr(split_buffer)); |
7f5c1516 | 1008 | btrfs_set_header_generation(&split->header, trans->transid); |
4d775673 | 1009 | btrfs_set_header_owner(&split->header, root->root_key.objectid); |
3eb0314d CM |
1010 | memcpy(split->header.fsid, root->fs_info->disk_super->fsid, |
1011 | sizeof(split->header.fsid)); | |
7518a238 | 1012 | mid = (c_nritems + 1) / 2; |
d6025579 CM |
1013 | btrfs_memcpy(root, split, split->ptrs, c->ptrs + mid, |
1014 | (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); | |
7518a238 CM |
1015 | btrfs_set_header_nritems(&split->header, c_nritems - mid); |
1016 | btrfs_set_header_nritems(&c->header, mid); | |
aa5d6bed CM |
1017 | ret = 0; |
1018 | ||
d6025579 CM |
1019 | btrfs_mark_buffer_dirty(t); |
1020 | btrfs_mark_buffer_dirty(split_buffer); | |
e089f05c | 1021 | wret = insert_ptr(trans, root, path, &split->ptrs[0].key, |
7eccb903 | 1022 | bh_blocknr(split_buffer), path->slots[level + 1] + 1, |
123abc88 | 1023 | level + 1); |
aa5d6bed CM |
1024 | if (wret) |
1025 | ret = wret; | |
1026 | ||
5de08d7d | 1027 | if (path->slots[level] >= mid) { |
5c680ed6 | 1028 | path->slots[level] -= mid; |
234b63a0 | 1029 | btrfs_block_release(root, t); |
5c680ed6 CM |
1030 | path->nodes[level] = split_buffer; |
1031 | path->slots[level + 1] += 1; | |
1032 | } else { | |
234b63a0 | 1033 | btrfs_block_release(root, split_buffer); |
be0e5c09 | 1034 | } |
aa5d6bed | 1035 | return ret; |
be0e5c09 CM |
1036 | } |
1037 | ||
74123bd7 CM |
1038 | /* |
1039 | * how many bytes are required to store the items in a leaf. start | |
1040 | * and nr indicate which items in the leaf to check. This totals up the | |
1041 | * space used both by the item structs and the item data | |
1042 | */ | |
234b63a0 | 1043 | static int leaf_space_used(struct btrfs_leaf *l, int start, int nr) |
be0e5c09 CM |
1044 | { |
1045 | int data_len; | |
d4dbff95 CM |
1046 | int nritems = btrfs_header_nritems(&l->header); |
1047 | int end = min(nritems, start + nr) - 1; | |
be0e5c09 CM |
1048 | |
1049 | if (!nr) | |
1050 | return 0; | |
0783fcfc CM |
1051 | data_len = btrfs_item_end(l->items + start); |
1052 | data_len = data_len - btrfs_item_offset(l->items + end); | |
1053 | data_len += sizeof(struct btrfs_item) * nr; | |
d4dbff95 | 1054 | WARN_ON(data_len < 0); |
be0e5c09 CM |
1055 | return data_len; |
1056 | } | |
1057 | ||
d4dbff95 CM |
1058 | /* |
1059 | * The space between the end of the leaf items and | |
1060 | * the start of the leaf data. IOW, how much room | |
1061 | * the leaf has left for both items and data | |
1062 | */ | |
1063 | int btrfs_leaf_free_space(struct btrfs_root *root, struct btrfs_leaf *leaf) | |
1064 | { | |
1065 | int nritems = btrfs_header_nritems(&leaf->header); | |
1066 | return BTRFS_LEAF_DATA_SIZE(root) - leaf_space_used(leaf, 0, nritems); | |
1067 | } | |
1068 | ||
00ec4c51 CM |
1069 | /* |
1070 | * push some data in the path leaf to the right, trying to free up at | |
1071 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
aa5d6bed CM |
1072 | * |
1073 | * returns 1 if the push failed because the other node didn't have enough | |
1074 | * room, 0 if everything worked out and < 0 if there were major errors. | |
00ec4c51 | 1075 | */ |
e089f05c CM |
1076 | static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root |
1077 | *root, struct btrfs_path *path, int data_size) | |
00ec4c51 | 1078 | { |
e20d96d6 CM |
1079 | struct buffer_head *left_buf = path->nodes[0]; |
1080 | struct btrfs_leaf *left = btrfs_buffer_leaf(left_buf); | |
234b63a0 | 1081 | struct btrfs_leaf *right; |
e20d96d6 CM |
1082 | struct buffer_head *right_buf; |
1083 | struct buffer_head *upper; | |
1084 | struct btrfs_node *upper_node; | |
00ec4c51 CM |
1085 | int slot; |
1086 | int i; | |
1087 | int free_space; | |
1088 | int push_space = 0; | |
1089 | int push_items = 0; | |
0783fcfc | 1090 | struct btrfs_item *item; |
7518a238 CM |
1091 | u32 left_nritems; |
1092 | u32 right_nritems; | |
54aa1f4d | 1093 | int ret; |
00ec4c51 CM |
1094 | |
1095 | slot = path->slots[1]; | |
1096 | if (!path->nodes[1]) { | |
1097 | return 1; | |
1098 | } | |
1099 | upper = path->nodes[1]; | |
e20d96d6 CM |
1100 | upper_node = btrfs_buffer_node(upper); |
1101 | if (slot >= btrfs_header_nritems(&upper_node->header) - 1) { | |
00ec4c51 CM |
1102 | return 1; |
1103 | } | |
e20d96d6 CM |
1104 | right_buf = read_tree_block(root, |
1105 | btrfs_node_blockptr(btrfs_buffer_node(upper), slot + 1)); | |
1106 | right = btrfs_buffer_leaf(right_buf); | |
123abc88 | 1107 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 1108 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1109 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
1110 | return 1; |
1111 | } | |
02217ed2 | 1112 | /* cow and double check */ |
54aa1f4d CM |
1113 | ret = btrfs_cow_block(trans, root, right_buf, upper, |
1114 | slot + 1, &right_buf); | |
1115 | if (ret) { | |
1116 | btrfs_block_release(root, right_buf); | |
1117 | return 1; | |
1118 | } | |
e20d96d6 | 1119 | right = btrfs_buffer_leaf(right_buf); |
123abc88 | 1120 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 1121 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1122 | btrfs_block_release(root, right_buf); |
02217ed2 CM |
1123 | return 1; |
1124 | } | |
1125 | ||
7518a238 | 1126 | left_nritems = btrfs_header_nritems(&left->header); |
a429e513 CM |
1127 | if (left_nritems == 0) { |
1128 | btrfs_block_release(root, right_buf); | |
1129 | return 1; | |
1130 | } | |
1131 | for (i = left_nritems - 1; i >= 1; i--) { | |
00ec4c51 CM |
1132 | item = left->items + i; |
1133 | if (path->slots[0] == i) | |
1134 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
1135 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
1136 | free_space) | |
00ec4c51 CM |
1137 | break; |
1138 | push_items++; | |
0783fcfc | 1139 | push_space += btrfs_item_size(item) + sizeof(*item); |
00ec4c51 CM |
1140 | } |
1141 | if (push_items == 0) { | |
234b63a0 | 1142 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
1143 | return 1; |
1144 | } | |
a429e513 CM |
1145 | if (push_items == left_nritems) |
1146 | WARN_ON(1); | |
7518a238 | 1147 | right_nritems = btrfs_header_nritems(&right->header); |
00ec4c51 | 1148 | /* push left to right */ |
0783fcfc | 1149 | push_space = btrfs_item_end(left->items + left_nritems - push_items); |
123abc88 | 1150 | push_space -= leaf_data_end(root, left); |
00ec4c51 | 1151 | /* make room in the right data area */ |
d6025579 CM |
1152 | btrfs_memmove(root, right, btrfs_leaf_data(right) + |
1153 | leaf_data_end(root, right) - push_space, | |
1154 | btrfs_leaf_data(right) + | |
1155 | leaf_data_end(root, right), BTRFS_LEAF_DATA_SIZE(root) - | |
1156 | leaf_data_end(root, right)); | |
00ec4c51 | 1157 | /* copy from the left data area */ |
d6025579 CM |
1158 | btrfs_memcpy(root, right, btrfs_leaf_data(right) + |
1159 | BTRFS_LEAF_DATA_SIZE(root) - push_space, | |
1160 | btrfs_leaf_data(left) + leaf_data_end(root, left), | |
1161 | push_space); | |
1162 | btrfs_memmove(root, right, right->items + push_items, right->items, | |
0783fcfc | 1163 | right_nritems * sizeof(struct btrfs_item)); |
00ec4c51 | 1164 | /* copy the items from left to right */ |
d6025579 CM |
1165 | btrfs_memcpy(root, right, right->items, left->items + |
1166 | left_nritems - push_items, | |
1167 | push_items * sizeof(struct btrfs_item)); | |
00ec4c51 CM |
1168 | |
1169 | /* update the item pointers */ | |
7518a238 CM |
1170 | right_nritems += push_items; |
1171 | btrfs_set_header_nritems(&right->header, right_nritems); | |
123abc88 | 1172 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
7518a238 | 1173 | for (i = 0; i < right_nritems; i++) { |
0783fcfc CM |
1174 | btrfs_set_item_offset(right->items + i, push_space - |
1175 | btrfs_item_size(right->items + i)); | |
1176 | push_space = btrfs_item_offset(right->items + i); | |
00ec4c51 | 1177 | } |
7518a238 CM |
1178 | left_nritems -= push_items; |
1179 | btrfs_set_header_nritems(&left->header, left_nritems); | |
00ec4c51 | 1180 | |
d6025579 CM |
1181 | btrfs_mark_buffer_dirty(left_buf); |
1182 | btrfs_mark_buffer_dirty(right_buf); | |
a429e513 | 1183 | |
d6025579 | 1184 | btrfs_memcpy(root, upper_node, &upper_node->ptrs[slot + 1].key, |
e2fa7227 | 1185 | &right->items[0].key, sizeof(struct btrfs_disk_key)); |
d6025579 | 1186 | btrfs_mark_buffer_dirty(upper); |
02217ed2 | 1187 | |
00ec4c51 | 1188 | /* then fixup the leaf pointer in the path */ |
7518a238 CM |
1189 | if (path->slots[0] >= left_nritems) { |
1190 | path->slots[0] -= left_nritems; | |
234b63a0 | 1191 | btrfs_block_release(root, path->nodes[0]); |
00ec4c51 CM |
1192 | path->nodes[0] = right_buf; |
1193 | path->slots[1] += 1; | |
1194 | } else { | |
234b63a0 | 1195 | btrfs_block_release(root, right_buf); |
00ec4c51 | 1196 | } |
098f59c2 CM |
1197 | if (path->nodes[1]) |
1198 | check_node(root, path, 1); | |
00ec4c51 CM |
1199 | return 0; |
1200 | } | |
74123bd7 CM |
1201 | /* |
1202 | * push some data in the path leaf to the left, trying to free up at | |
1203 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
1204 | */ | |
e089f05c CM |
1205 | static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root |
1206 | *root, struct btrfs_path *path, int data_size) | |
be0e5c09 | 1207 | { |
e20d96d6 CM |
1208 | struct buffer_head *right_buf = path->nodes[0]; |
1209 | struct btrfs_leaf *right = btrfs_buffer_leaf(right_buf); | |
1210 | struct buffer_head *t; | |
234b63a0 | 1211 | struct btrfs_leaf *left; |
be0e5c09 CM |
1212 | int slot; |
1213 | int i; | |
1214 | int free_space; | |
1215 | int push_space = 0; | |
1216 | int push_items = 0; | |
0783fcfc | 1217 | struct btrfs_item *item; |
7518a238 | 1218 | u32 old_left_nritems; |
aa5d6bed CM |
1219 | int ret = 0; |
1220 | int wret; | |
be0e5c09 CM |
1221 | |
1222 | slot = path->slots[1]; | |
1223 | if (slot == 0) { | |
1224 | return 1; | |
1225 | } | |
1226 | if (!path->nodes[1]) { | |
1227 | return 1; | |
1228 | } | |
e20d96d6 CM |
1229 | t = read_tree_block(root, |
1230 | btrfs_node_blockptr(btrfs_buffer_node(path->nodes[1]), slot - 1)); | |
1231 | left = btrfs_buffer_leaf(t); | |
123abc88 | 1232 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 1233 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1234 | btrfs_block_release(root, t); |
be0e5c09 CM |
1235 | return 1; |
1236 | } | |
02217ed2 CM |
1237 | |
1238 | /* cow and double check */ | |
54aa1f4d CM |
1239 | ret = btrfs_cow_block(trans, root, t, path->nodes[1], slot - 1, &t); |
1240 | if (ret) { | |
1241 | /* we hit -ENOSPC, but it isn't fatal here */ | |
1242 | return 1; | |
1243 | } | |
e20d96d6 | 1244 | left = btrfs_buffer_leaf(t); |
123abc88 | 1245 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 1246 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1247 | btrfs_block_release(root, t); |
02217ed2 CM |
1248 | return 1; |
1249 | } | |
1250 | ||
a429e513 CM |
1251 | if (btrfs_header_nritems(&right->header) == 0) { |
1252 | btrfs_block_release(root, t); | |
1253 | return 1; | |
1254 | } | |
1255 | ||
1256 | for (i = 0; i < btrfs_header_nritems(&right->header) - 1; i++) { | |
be0e5c09 CM |
1257 | item = right->items + i; |
1258 | if (path->slots[0] == i) | |
1259 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
1260 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
1261 | free_space) | |
be0e5c09 CM |
1262 | break; |
1263 | push_items++; | |
0783fcfc | 1264 | push_space += btrfs_item_size(item) + sizeof(*item); |
be0e5c09 CM |
1265 | } |
1266 | if (push_items == 0) { | |
234b63a0 | 1267 | btrfs_block_release(root, t); |
be0e5c09 CM |
1268 | return 1; |
1269 | } | |
a429e513 CM |
1270 | if (push_items == btrfs_header_nritems(&right->header)) |
1271 | WARN_ON(1); | |
be0e5c09 | 1272 | /* push data from right to left */ |
d6025579 CM |
1273 | btrfs_memcpy(root, left, left->items + |
1274 | btrfs_header_nritems(&left->header), | |
1275 | right->items, push_items * sizeof(struct btrfs_item)); | |
123abc88 | 1276 | push_space = BTRFS_LEAF_DATA_SIZE(root) - |
0783fcfc | 1277 | btrfs_item_offset(right->items + push_items -1); |
d6025579 CM |
1278 | btrfs_memcpy(root, left, btrfs_leaf_data(left) + |
1279 | leaf_data_end(root, left) - push_space, | |
1280 | btrfs_leaf_data(right) + | |
1281 | btrfs_item_offset(right->items + push_items - 1), | |
1282 | push_space); | |
7518a238 | 1283 | old_left_nritems = btrfs_header_nritems(&left->header); |
eb60ceac CM |
1284 | BUG_ON(old_left_nritems < 0); |
1285 | ||
0783fcfc | 1286 | for (i = old_left_nritems; i < old_left_nritems + push_items; i++) { |
123abc88 CM |
1287 | u32 ioff = btrfs_item_offset(left->items + i); |
1288 | btrfs_set_item_offset(left->items + i, ioff - | |
1289 | (BTRFS_LEAF_DATA_SIZE(root) - | |
0783fcfc CM |
1290 | btrfs_item_offset(left->items + |
1291 | old_left_nritems - 1))); | |
be0e5c09 | 1292 | } |
7518a238 | 1293 | btrfs_set_header_nritems(&left->header, old_left_nritems + push_items); |
be0e5c09 CM |
1294 | |
1295 | /* fixup right node */ | |
0783fcfc | 1296 | push_space = btrfs_item_offset(right->items + push_items - 1) - |
123abc88 | 1297 | leaf_data_end(root, right); |
d6025579 CM |
1298 | btrfs_memmove(root, right, btrfs_leaf_data(right) + |
1299 | BTRFS_LEAF_DATA_SIZE(root) - push_space, | |
1300 | btrfs_leaf_data(right) + | |
1301 | leaf_data_end(root, right), push_space); | |
1302 | btrfs_memmove(root, right, right->items, right->items + push_items, | |
7518a238 | 1303 | (btrfs_header_nritems(&right->header) - push_items) * |
0783fcfc | 1304 | sizeof(struct btrfs_item)); |
7518a238 CM |
1305 | btrfs_set_header_nritems(&right->header, |
1306 | btrfs_header_nritems(&right->header) - | |
1307 | push_items); | |
123abc88 | 1308 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
eb60ceac | 1309 | |
7518a238 | 1310 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
0783fcfc CM |
1311 | btrfs_set_item_offset(right->items + i, push_space - |
1312 | btrfs_item_size(right->items + i)); | |
1313 | push_space = btrfs_item_offset(right->items + i); | |
be0e5c09 | 1314 | } |
eb60ceac | 1315 | |
d6025579 CM |
1316 | btrfs_mark_buffer_dirty(t); |
1317 | btrfs_mark_buffer_dirty(right_buf); | |
098f59c2 | 1318 | |
e089f05c | 1319 | wret = fixup_low_keys(trans, root, path, &right->items[0].key, 1); |
aa5d6bed CM |
1320 | if (wret) |
1321 | ret = wret; | |
be0e5c09 CM |
1322 | |
1323 | /* then fixup the leaf pointer in the path */ | |
1324 | if (path->slots[0] < push_items) { | |
1325 | path->slots[0] += old_left_nritems; | |
234b63a0 | 1326 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1327 | path->nodes[0] = t; |
be0e5c09 CM |
1328 | path->slots[1] -= 1; |
1329 | } else { | |
234b63a0 | 1330 | btrfs_block_release(root, t); |
be0e5c09 CM |
1331 | path->slots[0] -= push_items; |
1332 | } | |
eb60ceac | 1333 | BUG_ON(path->slots[0] < 0); |
098f59c2 CM |
1334 | if (path->nodes[1]) |
1335 | check_node(root, path, 1); | |
aa5d6bed | 1336 | return ret; |
be0e5c09 CM |
1337 | } |
1338 | ||
74123bd7 CM |
1339 | /* |
1340 | * split the path's leaf in two, making sure there is at least data_size | |
1341 | * available for the resulting leaf level of the path. | |
aa5d6bed CM |
1342 | * |
1343 | * returns 0 if all went well and < 0 on failure. | |
74123bd7 | 1344 | */ |
e089f05c | 1345 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root |
d4dbff95 CM |
1346 | *root, struct btrfs_key *ins_key, |
1347 | struct btrfs_path *path, int data_size) | |
be0e5c09 | 1348 | { |
e20d96d6 | 1349 | struct buffer_head *l_buf; |
234b63a0 | 1350 | struct btrfs_leaf *l; |
7518a238 | 1351 | u32 nritems; |
eb60ceac CM |
1352 | int mid; |
1353 | int slot; | |
234b63a0 | 1354 | struct btrfs_leaf *right; |
e20d96d6 | 1355 | struct buffer_head *right_buffer; |
0783fcfc | 1356 | int space_needed = data_size + sizeof(struct btrfs_item); |
be0e5c09 CM |
1357 | int data_copy_size; |
1358 | int rt_data_off; | |
1359 | int i; | |
d4dbff95 | 1360 | int ret = 0; |
aa5d6bed | 1361 | int wret; |
d4dbff95 CM |
1362 | int double_split = 0; |
1363 | struct btrfs_disk_key disk_key; | |
aa5d6bed | 1364 | |
40689478 | 1365 | /* first try to make some room by pushing left and right */ |
e089f05c | 1366 | wret = push_leaf_left(trans, root, path, data_size); |
eaee50e8 CM |
1367 | if (wret < 0) |
1368 | return wret; | |
1369 | if (wret) { | |
e089f05c | 1370 | wret = push_leaf_right(trans, root, path, data_size); |
eaee50e8 CM |
1371 | if (wret < 0) |
1372 | return wret; | |
1373 | } | |
aa5d6bed | 1374 | l_buf = path->nodes[0]; |
e20d96d6 | 1375 | l = btrfs_buffer_leaf(l_buf); |
aa5d6bed CM |
1376 | |
1377 | /* did the pushes work? */ | |
123abc88 CM |
1378 | if (btrfs_leaf_free_space(root, l) >= |
1379 | sizeof(struct btrfs_item) + data_size) | |
aa5d6bed CM |
1380 | return 0; |
1381 | ||
5c680ed6 | 1382 | if (!path->nodes[1]) { |
e089f05c | 1383 | ret = insert_new_root(trans, root, path, 1); |
5c680ed6 CM |
1384 | if (ret) |
1385 | return ret; | |
1386 | } | |
eb60ceac | 1387 | slot = path->slots[0]; |
7518a238 | 1388 | nritems = btrfs_header_nritems(&l->header); |
eb60ceac | 1389 | mid = (nritems + 1)/ 2; |
54aa1f4d | 1390 | |
31f3c99b | 1391 | right_buffer = btrfs_alloc_free_block(trans, root, l_buf->b_blocknr); |
54aa1f4d CM |
1392 | if (IS_ERR(right_buffer)) |
1393 | return PTR_ERR(right_buffer); | |
1394 | ||
e20d96d6 | 1395 | right = btrfs_buffer_leaf(right_buffer); |
123abc88 | 1396 | memset(&right->header, 0, sizeof(right->header)); |
7eccb903 | 1397 | btrfs_set_header_blocknr(&right->header, bh_blocknr(right_buffer)); |
7f5c1516 | 1398 | btrfs_set_header_generation(&right->header, trans->transid); |
4d775673 | 1399 | btrfs_set_header_owner(&right->header, root->root_key.objectid); |
7518a238 | 1400 | btrfs_set_header_level(&right->header, 0); |
3eb0314d CM |
1401 | memcpy(right->header.fsid, root->fs_info->disk_super->fsid, |
1402 | sizeof(right->header.fsid)); | |
d4dbff95 CM |
1403 | if (mid <= slot) { |
1404 | if (nritems == 1 || | |
1405 | leaf_space_used(l, mid, nritems - mid) + space_needed > | |
1406 | BTRFS_LEAF_DATA_SIZE(root)) { | |
1407 | if (slot >= nritems) { | |
1408 | btrfs_cpu_key_to_disk(&disk_key, ins_key); | |
1409 | btrfs_set_header_nritems(&right->header, 0); | |
1410 | wret = insert_ptr(trans, root, path, | |
1411 | &disk_key, | |
7eccb903 | 1412 | bh_blocknr(right_buffer), |
d4dbff95 CM |
1413 | path->slots[1] + 1, 1); |
1414 | if (wret) | |
1415 | ret = wret; | |
1416 | btrfs_block_release(root, path->nodes[0]); | |
1417 | path->nodes[0] = right_buffer; | |
1418 | path->slots[0] = 0; | |
1419 | path->slots[1] += 1; | |
1420 | return ret; | |
1421 | } | |
1422 | mid = slot; | |
1423 | double_split = 1; | |
1424 | } | |
1425 | } else { | |
1426 | if (leaf_space_used(l, 0, mid + 1) + space_needed > | |
1427 | BTRFS_LEAF_DATA_SIZE(root)) { | |
1428 | if (slot == 0) { | |
1429 | btrfs_cpu_key_to_disk(&disk_key, ins_key); | |
1430 | btrfs_set_header_nritems(&right->header, 0); | |
1431 | wret = insert_ptr(trans, root, path, | |
1432 | &disk_key, | |
7eccb903 | 1433 | bh_blocknr(right_buffer), |
098f59c2 | 1434 | path->slots[1], 1); |
d4dbff95 CM |
1435 | if (wret) |
1436 | ret = wret; | |
1437 | btrfs_block_release(root, path->nodes[0]); | |
1438 | path->nodes[0] = right_buffer; | |
1439 | path->slots[0] = 0; | |
a429e513 CM |
1440 | if (path->slots[1] == 0) { |
1441 | wret = fixup_low_keys(trans, root, | |
1442 | path, &disk_key, 1); | |
1443 | if (wret) | |
1444 | ret = wret; | |
1445 | } | |
d4dbff95 CM |
1446 | return ret; |
1447 | } | |
1448 | mid = slot; | |
1449 | double_split = 1; | |
1450 | } | |
1451 | } | |
1452 | btrfs_set_header_nritems(&right->header, nritems - mid); | |
123abc88 CM |
1453 | data_copy_size = btrfs_item_end(l->items + mid) - |
1454 | leaf_data_end(root, l); | |
d6025579 CM |
1455 | btrfs_memcpy(root, right, right->items, l->items + mid, |
1456 | (nritems - mid) * sizeof(struct btrfs_item)); | |
1457 | btrfs_memcpy(root, right, | |
1458 | btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - | |
1459 | data_copy_size, btrfs_leaf_data(l) + | |
1460 | leaf_data_end(root, l), data_copy_size); | |
123abc88 CM |
1461 | rt_data_off = BTRFS_LEAF_DATA_SIZE(root) - |
1462 | btrfs_item_end(l->items + mid); | |
74123bd7 | 1463 | |
0783fcfc | 1464 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
123abc88 | 1465 | u32 ioff = btrfs_item_offset(right->items + i); |
0783fcfc CM |
1466 | btrfs_set_item_offset(right->items + i, ioff + rt_data_off); |
1467 | } | |
74123bd7 | 1468 | |
7518a238 | 1469 | btrfs_set_header_nritems(&l->header, mid); |
aa5d6bed | 1470 | ret = 0; |
e089f05c | 1471 | wret = insert_ptr(trans, root, path, &right->items[0].key, |
7eccb903 | 1472 | bh_blocknr(right_buffer), path->slots[1] + 1, 1); |
aa5d6bed CM |
1473 | if (wret) |
1474 | ret = wret; | |
d6025579 CM |
1475 | btrfs_mark_buffer_dirty(right_buffer); |
1476 | btrfs_mark_buffer_dirty(l_buf); | |
eb60ceac | 1477 | BUG_ON(path->slots[0] != slot); |
be0e5c09 | 1478 | if (mid <= slot) { |
234b63a0 | 1479 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1480 | path->nodes[0] = right_buffer; |
be0e5c09 CM |
1481 | path->slots[0] -= mid; |
1482 | path->slots[1] += 1; | |
eb60ceac | 1483 | } else |
234b63a0 | 1484 | btrfs_block_release(root, right_buffer); |
eb60ceac | 1485 | BUG_ON(path->slots[0] < 0); |
098f59c2 | 1486 | check_node(root, path, 1); |
d4dbff95 CM |
1487 | |
1488 | if (!double_split) | |
1489 | return ret; | |
31f3c99b | 1490 | right_buffer = btrfs_alloc_free_block(trans, root, l_buf->b_blocknr); |
54aa1f4d CM |
1491 | if (IS_ERR(right_buffer)) |
1492 | return PTR_ERR(right_buffer); | |
1493 | ||
d4dbff95 CM |
1494 | right = btrfs_buffer_leaf(right_buffer); |
1495 | memset(&right->header, 0, sizeof(right->header)); | |
7eccb903 | 1496 | btrfs_set_header_blocknr(&right->header, bh_blocknr(right_buffer)); |
d4dbff95 | 1497 | btrfs_set_header_generation(&right->header, trans->transid); |
4d775673 | 1498 | btrfs_set_header_owner(&right->header, root->root_key.objectid); |
d4dbff95 | 1499 | btrfs_set_header_level(&right->header, 0); |
3eb0314d CM |
1500 | memcpy(right->header.fsid, root->fs_info->disk_super->fsid, |
1501 | sizeof(right->header.fsid)); | |
d4dbff95 CM |
1502 | btrfs_cpu_key_to_disk(&disk_key, ins_key); |
1503 | btrfs_set_header_nritems(&right->header, 0); | |
1504 | wret = insert_ptr(trans, root, path, | |
1505 | &disk_key, | |
7eccb903 | 1506 | bh_blocknr(right_buffer), |
d4dbff95 CM |
1507 | path->slots[1], 1); |
1508 | if (wret) | |
1509 | ret = wret; | |
a429e513 CM |
1510 | if (path->slots[1] == 0) { |
1511 | wret = fixup_low_keys(trans, root, path, &disk_key, 1); | |
1512 | if (wret) | |
1513 | ret = wret; | |
1514 | } | |
d4dbff95 CM |
1515 | btrfs_block_release(root, path->nodes[0]); |
1516 | path->nodes[0] = right_buffer; | |
1517 | path->slots[0] = 0; | |
1518 | check_node(root, path, 1); | |
1519 | check_leaf(root, path, 0); | |
be0e5c09 CM |
1520 | return ret; |
1521 | } | |
1522 | ||
b18c6685 CM |
1523 | int btrfs_truncate_item(struct btrfs_trans_handle *trans, |
1524 | struct btrfs_root *root, | |
1525 | struct btrfs_path *path, | |
1526 | u32 new_size) | |
1527 | { | |
1528 | int ret = 0; | |
1529 | int slot; | |
1530 | int slot_orig; | |
1531 | struct btrfs_leaf *leaf; | |
1532 | struct buffer_head *leaf_buf; | |
1533 | u32 nritems; | |
1534 | unsigned int data_end; | |
1535 | unsigned int old_data_start; | |
1536 | unsigned int old_size; | |
1537 | unsigned int size_diff; | |
1538 | int i; | |
1539 | ||
1540 | slot_orig = path->slots[0]; | |
1541 | leaf_buf = path->nodes[0]; | |
1542 | leaf = btrfs_buffer_leaf(leaf_buf); | |
1543 | ||
1544 | nritems = btrfs_header_nritems(&leaf->header); | |
1545 | data_end = leaf_data_end(root, leaf); | |
1546 | ||
1547 | slot = path->slots[0]; | |
1548 | old_data_start = btrfs_item_offset(leaf->items + slot); | |
1549 | old_size = btrfs_item_size(leaf->items + slot); | |
1550 | BUG_ON(old_size <= new_size); | |
1551 | size_diff = old_size - new_size; | |
1552 | ||
1553 | BUG_ON(slot < 0); | |
1554 | BUG_ON(slot >= nritems); | |
1555 | ||
1556 | /* | |
1557 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1558 | */ | |
1559 | /* first correct the data pointers */ | |
1560 | for (i = slot; i < nritems; i++) { | |
1561 | u32 ioff = btrfs_item_offset(leaf->items + i); | |
1562 | btrfs_set_item_offset(leaf->items + i, | |
1563 | ioff + size_diff); | |
1564 | } | |
1565 | /* shift the data */ | |
b18c6685 CM |
1566 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + |
1567 | data_end + size_diff, btrfs_leaf_data(leaf) + | |
1568 | data_end, old_data_start + new_size - data_end); | |
1569 | btrfs_set_item_size(leaf->items + slot, new_size); | |
1570 | btrfs_mark_buffer_dirty(leaf_buf); | |
1571 | ||
1572 | ret = 0; | |
1573 | if (btrfs_leaf_free_space(root, leaf) < 0) | |
1574 | BUG(); | |
1575 | check_leaf(root, path, 0); | |
1576 | return ret; | |
1577 | } | |
1578 | ||
6567e837 CM |
1579 | int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1580 | *root, struct btrfs_path *path, u32 data_size) | |
1581 | { | |
1582 | int ret = 0; | |
1583 | int slot; | |
1584 | int slot_orig; | |
1585 | struct btrfs_leaf *leaf; | |
1586 | struct buffer_head *leaf_buf; | |
1587 | u32 nritems; | |
1588 | unsigned int data_end; | |
1589 | unsigned int old_data; | |
1590 | unsigned int old_size; | |
1591 | int i; | |
1592 | ||
1593 | slot_orig = path->slots[0]; | |
1594 | leaf_buf = path->nodes[0]; | |
1595 | leaf = btrfs_buffer_leaf(leaf_buf); | |
1596 | ||
1597 | nritems = btrfs_header_nritems(&leaf->header); | |
1598 | data_end = leaf_data_end(root, leaf); | |
1599 | ||
1600 | if (btrfs_leaf_free_space(root, leaf) < data_size) | |
1601 | BUG(); | |
1602 | slot = path->slots[0]; | |
1603 | old_data = btrfs_item_end(leaf->items + slot); | |
1604 | ||
1605 | BUG_ON(slot < 0); | |
1606 | BUG_ON(slot >= nritems); | |
1607 | ||
1608 | /* | |
1609 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1610 | */ | |
1611 | /* first correct the data pointers */ | |
1612 | for (i = slot; i < nritems; i++) { | |
1613 | u32 ioff = btrfs_item_offset(leaf->items + i); | |
1614 | btrfs_set_item_offset(leaf->items + i, | |
1615 | ioff - data_size); | |
1616 | } | |
1617 | /* shift the data */ | |
1618 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + | |
1619 | data_end - data_size, btrfs_leaf_data(leaf) + | |
1620 | data_end, old_data - data_end); | |
1621 | data_end = old_data; | |
1622 | old_size = btrfs_item_size(leaf->items + slot); | |
1623 | btrfs_set_item_size(leaf->items + slot, old_size + data_size); | |
1624 | btrfs_mark_buffer_dirty(leaf_buf); | |
1625 | ||
1626 | ret = 0; | |
1627 | if (btrfs_leaf_free_space(root, leaf) < 0) | |
1628 | BUG(); | |
1629 | check_leaf(root, path, 0); | |
1630 | return ret; | |
1631 | } | |
1632 | ||
74123bd7 CM |
1633 | /* |
1634 | * Given a key and some data, insert an item into the tree. | |
1635 | * This does all the path init required, making room in the tree if needed. | |
1636 | */ | |
e089f05c CM |
1637 | int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1638 | *root, struct btrfs_path *path, struct btrfs_key | |
1639 | *cpu_key, u32 data_size) | |
be0e5c09 | 1640 | { |
aa5d6bed | 1641 | int ret = 0; |
be0e5c09 | 1642 | int slot; |
eb60ceac | 1643 | int slot_orig; |
234b63a0 | 1644 | struct btrfs_leaf *leaf; |
e20d96d6 | 1645 | struct buffer_head *leaf_buf; |
7518a238 | 1646 | u32 nritems; |
be0e5c09 | 1647 | unsigned int data_end; |
e2fa7227 CM |
1648 | struct btrfs_disk_key disk_key; |
1649 | ||
1650 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); | |
be0e5c09 | 1651 | |
74123bd7 | 1652 | /* create a root if there isn't one */ |
5c680ed6 | 1653 | if (!root->node) |
cfaa7295 | 1654 | BUG(); |
e089f05c | 1655 | ret = btrfs_search_slot(trans, root, cpu_key, path, data_size, 1); |
eb60ceac | 1656 | if (ret == 0) { |
f0930a37 | 1657 | return -EEXIST; |
aa5d6bed | 1658 | } |
ed2ff2cb CM |
1659 | if (ret < 0) |
1660 | goto out; | |
be0e5c09 | 1661 | |
62e2749e CM |
1662 | slot_orig = path->slots[0]; |
1663 | leaf_buf = path->nodes[0]; | |
e20d96d6 | 1664 | leaf = btrfs_buffer_leaf(leaf_buf); |
74123bd7 | 1665 | |
7518a238 | 1666 | nritems = btrfs_header_nritems(&leaf->header); |
123abc88 | 1667 | data_end = leaf_data_end(root, leaf); |
eb60ceac | 1668 | |
123abc88 | 1669 | if (btrfs_leaf_free_space(root, leaf) < |
d4dbff95 | 1670 | sizeof(struct btrfs_item) + data_size) { |
be0e5c09 | 1671 | BUG(); |
d4dbff95 | 1672 | } |
62e2749e | 1673 | slot = path->slots[0]; |
eb60ceac | 1674 | BUG_ON(slot < 0); |
be0e5c09 CM |
1675 | if (slot != nritems) { |
1676 | int i; | |
0783fcfc | 1677 | unsigned int old_data = btrfs_item_end(leaf->items + slot); |
be0e5c09 CM |
1678 | |
1679 | /* | |
1680 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1681 | */ | |
1682 | /* first correct the data pointers */ | |
0783fcfc | 1683 | for (i = slot; i < nritems; i++) { |
123abc88 | 1684 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
1685 | btrfs_set_item_offset(leaf->items + i, |
1686 | ioff - data_size); | |
1687 | } | |
be0e5c09 CM |
1688 | |
1689 | /* shift the items */ | |
d6025579 CM |
1690 | btrfs_memmove(root, leaf, leaf->items + slot + 1, |
1691 | leaf->items + slot, | |
1692 | (nritems - slot) * sizeof(struct btrfs_item)); | |
be0e5c09 CM |
1693 | |
1694 | /* shift the data */ | |
d6025579 CM |
1695 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + |
1696 | data_end - data_size, btrfs_leaf_data(leaf) + | |
1697 | data_end, old_data - data_end); | |
be0e5c09 CM |
1698 | data_end = old_data; |
1699 | } | |
62e2749e | 1700 | /* setup the item for the new data */ |
d6025579 CM |
1701 | btrfs_memcpy(root, leaf, &leaf->items[slot].key, &disk_key, |
1702 | sizeof(struct btrfs_disk_key)); | |
0783fcfc CM |
1703 | btrfs_set_item_offset(leaf->items + slot, data_end - data_size); |
1704 | btrfs_set_item_size(leaf->items + slot, data_size); | |
7518a238 | 1705 | btrfs_set_header_nritems(&leaf->header, nritems + 1); |
d6025579 | 1706 | btrfs_mark_buffer_dirty(leaf_buf); |
aa5d6bed CM |
1707 | |
1708 | ret = 0; | |
8e19f2cd | 1709 | if (slot == 0) |
e089f05c | 1710 | ret = fixup_low_keys(trans, root, path, &disk_key, 1); |
aa5d6bed | 1711 | |
123abc88 | 1712 | if (btrfs_leaf_free_space(root, leaf) < 0) |
be0e5c09 | 1713 | BUG(); |
62e2749e | 1714 | check_leaf(root, path, 0); |
ed2ff2cb | 1715 | out: |
62e2749e CM |
1716 | return ret; |
1717 | } | |
1718 | ||
1719 | /* | |
1720 | * Given a key and some data, insert an item into the tree. | |
1721 | * This does all the path init required, making room in the tree if needed. | |
1722 | */ | |
e089f05c CM |
1723 | int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1724 | *root, struct btrfs_key *cpu_key, void *data, u32 | |
1725 | data_size) | |
62e2749e CM |
1726 | { |
1727 | int ret = 0; | |
2c90e5d6 | 1728 | struct btrfs_path *path; |
62e2749e CM |
1729 | u8 *ptr; |
1730 | ||
2c90e5d6 CM |
1731 | path = btrfs_alloc_path(); |
1732 | BUG_ON(!path); | |
2c90e5d6 | 1733 | ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size); |
62e2749e | 1734 | if (!ret) { |
2c90e5d6 CM |
1735 | ptr = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), |
1736 | path->slots[0], u8); | |
1737 | btrfs_memcpy(root, path->nodes[0]->b_data, | |
d6025579 | 1738 | ptr, data, data_size); |
2c90e5d6 | 1739 | btrfs_mark_buffer_dirty(path->nodes[0]); |
62e2749e | 1740 | } |
2c90e5d6 | 1741 | btrfs_free_path(path); |
aa5d6bed | 1742 | return ret; |
be0e5c09 CM |
1743 | } |
1744 | ||
74123bd7 | 1745 | /* |
5de08d7d | 1746 | * delete the pointer from a given node. |
74123bd7 CM |
1747 | * |
1748 | * If the delete empties a node, the node is removed from the tree, | |
1749 | * continuing all the way the root if required. The root is converted into | |
1750 | * a leaf if all the nodes are emptied. | |
1751 | */ | |
e089f05c CM |
1752 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
1753 | struct btrfs_path *path, int level, int slot) | |
be0e5c09 | 1754 | { |
234b63a0 | 1755 | struct btrfs_node *node; |
e20d96d6 | 1756 | struct buffer_head *parent = path->nodes[level]; |
7518a238 | 1757 | u32 nritems; |
aa5d6bed | 1758 | int ret = 0; |
bb803951 | 1759 | int wret; |
be0e5c09 | 1760 | |
e20d96d6 | 1761 | node = btrfs_buffer_node(parent); |
7518a238 | 1762 | nritems = btrfs_header_nritems(&node->header); |
bb803951 | 1763 | if (slot != nritems -1) { |
d6025579 CM |
1764 | btrfs_memmove(root, node, node->ptrs + slot, |
1765 | node->ptrs + slot + 1, | |
1766 | sizeof(struct btrfs_key_ptr) * | |
1767 | (nritems - slot - 1)); | |
bb803951 | 1768 | } |
7518a238 CM |
1769 | nritems--; |
1770 | btrfs_set_header_nritems(&node->header, nritems); | |
1771 | if (nritems == 0 && parent == root->node) { | |
e20d96d6 CM |
1772 | struct btrfs_header *header = btrfs_buffer_header(root->node); |
1773 | BUG_ON(btrfs_header_level(header) != 1); | |
bb803951 | 1774 | /* just turn the root into a leaf and break */ |
e20d96d6 | 1775 | btrfs_set_header_level(header, 0); |
bb803951 | 1776 | } else if (slot == 0) { |
e089f05c | 1777 | wret = fixup_low_keys(trans, root, path, &node->ptrs[0].key, |
123abc88 | 1778 | level + 1); |
0f70abe2 CM |
1779 | if (wret) |
1780 | ret = wret; | |
be0e5c09 | 1781 | } |
d6025579 | 1782 | btrfs_mark_buffer_dirty(parent); |
aa5d6bed | 1783 | return ret; |
be0e5c09 CM |
1784 | } |
1785 | ||
74123bd7 CM |
1786 | /* |
1787 | * delete the item at the leaf level in path. If that empties | |
1788 | * the leaf, remove it from the tree | |
1789 | */ | |
e089f05c CM |
1790 | int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
1791 | struct btrfs_path *path) | |
be0e5c09 | 1792 | { |
be0e5c09 | 1793 | int slot; |
234b63a0 | 1794 | struct btrfs_leaf *leaf; |
e20d96d6 | 1795 | struct buffer_head *leaf_buf; |
be0e5c09 CM |
1796 | int doff; |
1797 | int dsize; | |
aa5d6bed CM |
1798 | int ret = 0; |
1799 | int wret; | |
7518a238 | 1800 | u32 nritems; |
be0e5c09 | 1801 | |
eb60ceac | 1802 | leaf_buf = path->nodes[0]; |
e20d96d6 | 1803 | leaf = btrfs_buffer_leaf(leaf_buf); |
4920c9ac | 1804 | slot = path->slots[0]; |
0783fcfc CM |
1805 | doff = btrfs_item_offset(leaf->items + slot); |
1806 | dsize = btrfs_item_size(leaf->items + slot); | |
7518a238 | 1807 | nritems = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 1808 | |
7518a238 | 1809 | if (slot != nritems - 1) { |
be0e5c09 | 1810 | int i; |
123abc88 | 1811 | int data_end = leaf_data_end(root, leaf); |
d6025579 CM |
1812 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + |
1813 | data_end + dsize, | |
1814 | btrfs_leaf_data(leaf) + data_end, | |
1815 | doff - data_end); | |
0783fcfc | 1816 | for (i = slot + 1; i < nritems; i++) { |
123abc88 | 1817 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
1818 | btrfs_set_item_offset(leaf->items + i, ioff + dsize); |
1819 | } | |
d6025579 CM |
1820 | btrfs_memmove(root, leaf, leaf->items + slot, |
1821 | leaf->items + slot + 1, | |
1822 | sizeof(struct btrfs_item) * | |
1823 | (nritems - slot - 1)); | |
be0e5c09 | 1824 | } |
7518a238 CM |
1825 | btrfs_set_header_nritems(&leaf->header, nritems - 1); |
1826 | nritems--; | |
74123bd7 | 1827 | /* delete the leaf if we've emptied it */ |
7518a238 | 1828 | if (nritems == 0) { |
eb60ceac | 1829 | if (leaf_buf == root->node) { |
7518a238 | 1830 | btrfs_set_header_level(&leaf->header, 0); |
9a8dd150 | 1831 | } else { |
e089f05c | 1832 | clean_tree_block(trans, root, leaf_buf); |
d6025579 | 1833 | wait_on_buffer(leaf_buf); |
e089f05c | 1834 | wret = del_ptr(trans, root, path, 1, path->slots[1]); |
aa5d6bed CM |
1835 | if (wret) |
1836 | ret = wret; | |
e089f05c | 1837 | wret = btrfs_free_extent(trans, root, |
7eccb903 | 1838 | bh_blocknr(leaf_buf), 1, 1); |
0f70abe2 CM |
1839 | if (wret) |
1840 | ret = wret; | |
9a8dd150 | 1841 | } |
be0e5c09 | 1842 | } else { |
7518a238 | 1843 | int used = leaf_space_used(leaf, 0, nritems); |
aa5d6bed | 1844 | if (slot == 0) { |
e089f05c CM |
1845 | wret = fixup_low_keys(trans, root, path, |
1846 | &leaf->items[0].key, 1); | |
aa5d6bed CM |
1847 | if (wret) |
1848 | ret = wret; | |
1849 | } | |
aa5d6bed | 1850 | |
74123bd7 | 1851 | /* delete the leaf if it is mostly empty */ |
123abc88 | 1852 | if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) { |
be0e5c09 CM |
1853 | /* push_leaf_left fixes the path. |
1854 | * make sure the path still points to our leaf | |
1855 | * for possible call to del_ptr below | |
1856 | */ | |
4920c9ac | 1857 | slot = path->slots[1]; |
e20d96d6 | 1858 | get_bh(leaf_buf); |
e089f05c | 1859 | wret = push_leaf_left(trans, root, path, 1); |
54aa1f4d | 1860 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed | 1861 | ret = wret; |
f0930a37 | 1862 | if (path->nodes[0] == leaf_buf && |
7518a238 | 1863 | btrfs_header_nritems(&leaf->header)) { |
e089f05c | 1864 | wret = push_leaf_right(trans, root, path, 1); |
54aa1f4d | 1865 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed CM |
1866 | ret = wret; |
1867 | } | |
7518a238 | 1868 | if (btrfs_header_nritems(&leaf->header) == 0) { |
7eccb903 | 1869 | u64 blocknr = bh_blocknr(leaf_buf); |
e089f05c | 1870 | clean_tree_block(trans, root, leaf_buf); |
d6025579 | 1871 | wait_on_buffer(leaf_buf); |
e089f05c | 1872 | wret = del_ptr(trans, root, path, 1, slot); |
aa5d6bed CM |
1873 | if (wret) |
1874 | ret = wret; | |
234b63a0 | 1875 | btrfs_block_release(root, leaf_buf); |
e089f05c CM |
1876 | wret = btrfs_free_extent(trans, root, blocknr, |
1877 | 1, 1); | |
0f70abe2 CM |
1878 | if (wret) |
1879 | ret = wret; | |
5de08d7d | 1880 | } else { |
d6025579 | 1881 | btrfs_mark_buffer_dirty(leaf_buf); |
234b63a0 | 1882 | btrfs_block_release(root, leaf_buf); |
be0e5c09 | 1883 | } |
d5719762 | 1884 | } else { |
d6025579 | 1885 | btrfs_mark_buffer_dirty(leaf_buf); |
be0e5c09 CM |
1886 | } |
1887 | } | |
aa5d6bed | 1888 | return ret; |
be0e5c09 CM |
1889 | } |
1890 | ||
97571fd0 CM |
1891 | /* |
1892 | * walk up the tree as far as required to find the next leaf. | |
0f70abe2 CM |
1893 | * returns 0 if it found something or 1 if there are no greater leaves. |
1894 | * returns < 0 on io errors. | |
97571fd0 | 1895 | */ |
234b63a0 | 1896 | int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) |
d97e63b6 CM |
1897 | { |
1898 | int slot; | |
1899 | int level = 1; | |
1900 | u64 blocknr; | |
e20d96d6 CM |
1901 | struct buffer_head *c; |
1902 | struct btrfs_node *c_node; | |
1903 | struct buffer_head *next = NULL; | |
d97e63b6 | 1904 | |
234b63a0 | 1905 | while(level < BTRFS_MAX_LEVEL) { |
d97e63b6 | 1906 | if (!path->nodes[level]) |
0f70abe2 | 1907 | return 1; |
d97e63b6 CM |
1908 | slot = path->slots[level] + 1; |
1909 | c = path->nodes[level]; | |
e20d96d6 CM |
1910 | c_node = btrfs_buffer_node(c); |
1911 | if (slot >= btrfs_header_nritems(&c_node->header)) { | |
d97e63b6 CM |
1912 | level++; |
1913 | continue; | |
1914 | } | |
e20d96d6 | 1915 | blocknr = btrfs_node_blockptr(c_node, slot); |
cfaa7295 | 1916 | if (next) |
234b63a0 | 1917 | btrfs_block_release(root, next); |
d97e63b6 CM |
1918 | next = read_tree_block(root, blocknr); |
1919 | break; | |
1920 | } | |
1921 | path->slots[level] = slot; | |
1922 | while(1) { | |
1923 | level--; | |
1924 | c = path->nodes[level]; | |
234b63a0 | 1925 | btrfs_block_release(root, c); |
d97e63b6 CM |
1926 | path->nodes[level] = next; |
1927 | path->slots[level] = 0; | |
1928 | if (!level) | |
1929 | break; | |
1d4f8a0c | 1930 | next = read_tree_block(root, |
e20d96d6 | 1931 | btrfs_node_blockptr(btrfs_buffer_node(next), 0)); |
d97e63b6 CM |
1932 | } |
1933 | return 0; | |
1934 | } |