Commit | Line | Data |
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be0e5c09 CM |
1 | #include <stdio.h> |
2 | #include <stdlib.h> | |
3 | #include "kerncompat.h" | |
eb60ceac CM |
4 | #include "radix-tree.h" |
5 | #include "ctree.h" | |
6 | #include "disk-io.h" | |
5de08d7d | 7 | #include "print-tree.h" |
9a8dd150 | 8 | |
234b63a0 | 9 | static int split_node(struct btrfs_root *root, struct btrfs_path *path, |
aa5d6bed | 10 | int level); |
234b63a0 | 11 | static int split_leaf(struct btrfs_root *root, struct btrfs_path *path, |
aa5d6bed | 12 | int data_size); |
234b63a0 CM |
13 | static int push_node_left(struct btrfs_root *root, struct btrfs_buffer *dst, |
14 | struct btrfs_buffer *src); | |
15 | static int balance_node_right(struct btrfs_root *root, | |
16 | struct btrfs_buffer *dst_buf, | |
17 | struct btrfs_buffer *src_buf); | |
18 | static int del_ptr(struct btrfs_root *root, struct btrfs_path *path, int level, | |
bb803951 | 19 | int slot); |
d97e63b6 | 20 | |
234b63a0 | 21 | inline void btrfs_init_path(struct btrfs_path *p) |
be0e5c09 CM |
22 | { |
23 | memset(p, 0, sizeof(*p)); | |
24 | } | |
25 | ||
234b63a0 | 26 | void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p) |
eb60ceac CM |
27 | { |
28 | int i; | |
234b63a0 | 29 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
eb60ceac CM |
30 | if (!p->nodes[i]) |
31 | break; | |
234b63a0 | 32 | btrfs_block_release(root, p->nodes[i]); |
eb60ceac | 33 | } |
aa5d6bed | 34 | memset(p, 0, sizeof(*p)); |
eb60ceac CM |
35 | } |
36 | ||
9aca1d51 | 37 | static int btrfs_cow_block(struct btrfs_root *root, |
234b63a0 CM |
38 | struct btrfs_buffer *buf, |
39 | struct btrfs_buffer *parent, | |
02217ed2 | 40 | int parent_slot, |
234b63a0 | 41 | struct btrfs_buffer **cow_ret) |
02217ed2 | 42 | { |
234b63a0 | 43 | struct btrfs_buffer *cow; |
02217ed2 CM |
44 | |
45 | if (!list_empty(&buf->dirty)) { | |
46 | *cow_ret = buf; | |
47 | return 0; | |
48 | } | |
234b63a0 | 49 | cow = btrfs_alloc_free_block(root); |
123abc88 | 50 | memcpy(&cow->node, &buf->node, root->blocksize); |
7518a238 | 51 | btrfs_set_header_blocknr(&cow->node.header, cow->blocknr); |
02217ed2 | 52 | *cow_ret = cow; |
a28ec197 | 53 | btrfs_inc_ref(root, buf); |
02217ed2 CM |
54 | if (buf == root->node) { |
55 | root->node = cow; | |
56 | cow->count++; | |
a28ec197 | 57 | if (buf != root->commit_root) |
234b63a0 CM |
58 | btrfs_free_extent(root, buf->blocknr, 1); |
59 | btrfs_block_release(root, buf); | |
02217ed2 | 60 | } else { |
1d4f8a0c CM |
61 | btrfs_set_node_blockptr(&parent->node, parent_slot, |
62 | cow->blocknr); | |
02217ed2 | 63 | BUG_ON(list_empty(&parent->dirty)); |
234b63a0 | 64 | btrfs_free_extent(root, buf->blocknr, 1); |
02217ed2 | 65 | } |
234b63a0 | 66 | btrfs_block_release(root, buf); |
02217ed2 CM |
67 | return 0; |
68 | } | |
69 | ||
74123bd7 CM |
70 | /* |
71 | * The leaf data grows from end-to-front in the node. | |
72 | * this returns the address of the start of the last item, | |
73 | * which is the stop of the leaf data stack | |
74 | */ | |
123abc88 CM |
75 | static inline unsigned int leaf_data_end(struct btrfs_root *root, |
76 | struct btrfs_leaf *leaf) | |
be0e5c09 | 77 | { |
7518a238 | 78 | u32 nr = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 79 | if (nr == 0) |
123abc88 | 80 | return BTRFS_LEAF_DATA_SIZE(root); |
0783fcfc | 81 | return btrfs_item_offset(leaf->items + nr - 1); |
be0e5c09 CM |
82 | } |
83 | ||
74123bd7 CM |
84 | /* |
85 | * The space between the end of the leaf items and | |
86 | * the start of the leaf data. IOW, how much room | |
87 | * the leaf has left for both items and data | |
88 | */ | |
123abc88 | 89 | int btrfs_leaf_free_space(struct btrfs_root *root, struct btrfs_leaf *leaf) |
be0e5c09 | 90 | { |
123abc88 | 91 | int data_end = leaf_data_end(root, leaf); |
7518a238 | 92 | int nritems = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 93 | char *items_end = (char *)(leaf->items + nritems + 1); |
123abc88 | 94 | return (char *)(btrfs_leaf_data(leaf) + data_end) - (char *)items_end; |
be0e5c09 CM |
95 | } |
96 | ||
74123bd7 CM |
97 | /* |
98 | * compare two keys in a memcmp fashion | |
99 | */ | |
9aca1d51 | 100 | static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2) |
be0e5c09 | 101 | { |
e2fa7227 CM |
102 | struct btrfs_key k1; |
103 | ||
104 | btrfs_disk_key_to_cpu(&k1, disk); | |
105 | ||
106 | if (k1.objectid > k2->objectid) | |
be0e5c09 | 107 | return 1; |
e2fa7227 | 108 | if (k1.objectid < k2->objectid) |
be0e5c09 | 109 | return -1; |
62e2749e CM |
110 | if (k1.flags > k2->flags) |
111 | return 1; | |
112 | if (k1.flags < k2->flags) | |
113 | return -1; | |
a8a2ee0c CM |
114 | if (k1.offset > k2->offset) |
115 | return 1; | |
116 | if (k1.offset < k2->offset) | |
117 | return -1; | |
be0e5c09 CM |
118 | return 0; |
119 | } | |
74123bd7 | 120 | |
123abc88 CM |
121 | static int check_node(struct btrfs_root *root, struct btrfs_path *path, |
122 | int level) | |
aa5d6bed CM |
123 | { |
124 | int i; | |
234b63a0 CM |
125 | struct btrfs_node *parent = NULL; |
126 | struct btrfs_node *node = &path->nodes[level]->node; | |
aa5d6bed | 127 | int parent_slot; |
7518a238 | 128 | u32 nritems = btrfs_header_nritems(&node->header); |
aa5d6bed CM |
129 | |
130 | if (path->nodes[level + 1]) | |
131 | parent = &path->nodes[level + 1]->node; | |
132 | parent_slot = path->slots[level + 1]; | |
7518a238 CM |
133 | BUG_ON(nritems == 0); |
134 | if (parent) { | |
e2fa7227 | 135 | struct btrfs_disk_key *parent_key; |
123abc88 CM |
136 | parent_key = &parent->ptrs[parent_slot].key; |
137 | BUG_ON(memcmp(parent_key, &node->ptrs[0].key, | |
e2fa7227 | 138 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 139 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
7518a238 | 140 | btrfs_header_blocknr(&node->header)); |
aa5d6bed | 141 | } |
123abc88 | 142 | BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root)); |
7518a238 | 143 | for (i = 0; nritems > 1 && i < nritems - 2; i++) { |
e2fa7227 | 144 | struct btrfs_key cpukey; |
123abc88 CM |
145 | btrfs_disk_key_to_cpu(&cpukey, &node->ptrs[i + 1].key); |
146 | BUG_ON(comp_keys(&node->ptrs[i].key, &cpukey) >= 0); | |
aa5d6bed CM |
147 | } |
148 | return 0; | |
149 | } | |
150 | ||
123abc88 CM |
151 | static int check_leaf(struct btrfs_root *root, struct btrfs_path *path, |
152 | int level) | |
aa5d6bed CM |
153 | { |
154 | int i; | |
234b63a0 CM |
155 | struct btrfs_leaf *leaf = &path->nodes[level]->leaf; |
156 | struct btrfs_node *parent = NULL; | |
aa5d6bed | 157 | int parent_slot; |
7518a238 | 158 | u32 nritems = btrfs_header_nritems(&leaf->header); |
aa5d6bed CM |
159 | |
160 | if (path->nodes[level + 1]) | |
161 | parent = &path->nodes[level + 1]->node; | |
162 | parent_slot = path->slots[level + 1]; | |
123abc88 | 163 | BUG_ON(btrfs_leaf_free_space(root, leaf) < 0); |
7518a238 CM |
164 | |
165 | if (nritems == 0) | |
166 | return 0; | |
167 | ||
168 | if (parent) { | |
e2fa7227 | 169 | struct btrfs_disk_key *parent_key; |
123abc88 | 170 | parent_key = &parent->ptrs[parent_slot].key; |
aa5d6bed | 171 | BUG_ON(memcmp(parent_key, &leaf->items[0].key, |
e2fa7227 | 172 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 173 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
7518a238 | 174 | btrfs_header_blocknr(&leaf->header)); |
aa5d6bed | 175 | } |
7518a238 | 176 | for (i = 0; nritems > 1 && i < nritems - 2; i++) { |
e2fa7227 CM |
177 | struct btrfs_key cpukey; |
178 | btrfs_disk_key_to_cpu(&cpukey, &leaf->items[i + 1].key); | |
aa5d6bed | 179 | BUG_ON(comp_keys(&leaf->items[i].key, |
e2fa7227 | 180 | &cpukey) >= 0); |
0783fcfc CM |
181 | BUG_ON(btrfs_item_offset(leaf->items + i) != |
182 | btrfs_item_end(leaf->items + i + 1)); | |
aa5d6bed | 183 | if (i == 0) { |
0783fcfc CM |
184 | BUG_ON(btrfs_item_offset(leaf->items + i) + |
185 | btrfs_item_size(leaf->items + i) != | |
123abc88 | 186 | BTRFS_LEAF_DATA_SIZE(root)); |
aa5d6bed CM |
187 | } |
188 | } | |
aa5d6bed CM |
189 | return 0; |
190 | } | |
191 | ||
123abc88 CM |
192 | static int check_block(struct btrfs_root *root, struct btrfs_path *path, |
193 | int level) | |
aa5d6bed CM |
194 | { |
195 | if (level == 0) | |
123abc88 CM |
196 | return check_leaf(root, path, level); |
197 | return check_node(root, path, level); | |
aa5d6bed CM |
198 | } |
199 | ||
74123bd7 CM |
200 | /* |
201 | * search for key in the array p. items p are item_size apart | |
202 | * and there are 'max' items in p | |
203 | * the slot in the array is returned via slot, and it points to | |
204 | * the place where you would insert key if it is not found in | |
205 | * the array. | |
206 | * | |
207 | * slot may point to max if the key is bigger than all of the keys | |
208 | */ | |
9aca1d51 | 209 | static int generic_bin_search(char *p, int item_size, struct btrfs_key *key, |
be0e5c09 CM |
210 | int max, int *slot) |
211 | { | |
212 | int low = 0; | |
213 | int high = max; | |
214 | int mid; | |
215 | int ret; | |
e2fa7227 | 216 | struct btrfs_disk_key *tmp; |
be0e5c09 CM |
217 | |
218 | while(low < high) { | |
219 | mid = (low + high) / 2; | |
e2fa7227 | 220 | tmp = (struct btrfs_disk_key *)(p + mid * item_size); |
be0e5c09 CM |
221 | ret = comp_keys(tmp, key); |
222 | ||
223 | if (ret < 0) | |
224 | low = mid + 1; | |
225 | else if (ret > 0) | |
226 | high = mid; | |
227 | else { | |
228 | *slot = mid; | |
229 | return 0; | |
230 | } | |
231 | } | |
232 | *slot = low; | |
233 | return 1; | |
234 | } | |
235 | ||
97571fd0 CM |
236 | /* |
237 | * simple bin_search frontend that does the right thing for | |
238 | * leaves vs nodes | |
239 | */ | |
9aca1d51 | 240 | static int bin_search(struct btrfs_node *c, struct btrfs_key *key, int *slot) |
be0e5c09 | 241 | { |
7518a238 | 242 | if (btrfs_is_leaf(c)) { |
234b63a0 | 243 | struct btrfs_leaf *l = (struct btrfs_leaf *)c; |
0783fcfc CM |
244 | return generic_bin_search((void *)l->items, |
245 | sizeof(struct btrfs_item), | |
7518a238 CM |
246 | key, btrfs_header_nritems(&c->header), |
247 | slot); | |
be0e5c09 | 248 | } else { |
123abc88 CM |
249 | return generic_bin_search((void *)c->ptrs, |
250 | sizeof(struct btrfs_key_ptr), | |
7518a238 CM |
251 | key, btrfs_header_nritems(&c->header), |
252 | slot); | |
be0e5c09 CM |
253 | } |
254 | return -1; | |
255 | } | |
256 | ||
9aca1d51 | 257 | static struct btrfs_buffer *read_node_slot(struct btrfs_root *root, |
234b63a0 | 258 | struct btrfs_buffer *parent_buf, |
bb803951 CM |
259 | int slot) |
260 | { | |
234b63a0 | 261 | struct btrfs_node *node = &parent_buf->node; |
bb803951 CM |
262 | if (slot < 0) |
263 | return NULL; | |
7518a238 | 264 | if (slot >= btrfs_header_nritems(&node->header)) |
bb803951 | 265 | return NULL; |
1d4f8a0c | 266 | return read_tree_block(root, btrfs_node_blockptr(node, slot)); |
bb803951 CM |
267 | } |
268 | ||
234b63a0 | 269 | static int balance_level(struct btrfs_root *root, struct btrfs_path *path, |
bb803951 CM |
270 | int level) |
271 | { | |
234b63a0 CM |
272 | struct btrfs_buffer *right_buf; |
273 | struct btrfs_buffer *mid_buf; | |
274 | struct btrfs_buffer *left_buf; | |
275 | struct btrfs_buffer *parent_buf = NULL; | |
276 | struct btrfs_node *right = NULL; | |
277 | struct btrfs_node *mid; | |
278 | struct btrfs_node *left = NULL; | |
279 | struct btrfs_node *parent = NULL; | |
bb803951 CM |
280 | int ret = 0; |
281 | int wret; | |
282 | int pslot; | |
bb803951 | 283 | int orig_slot = path->slots[level]; |
79f95c82 | 284 | u64 orig_ptr; |
bb803951 CM |
285 | |
286 | if (level == 0) | |
287 | return 0; | |
288 | ||
289 | mid_buf = path->nodes[level]; | |
290 | mid = &mid_buf->node; | |
1d4f8a0c | 291 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
79f95c82 | 292 | |
234b63a0 | 293 | if (level < BTRFS_MAX_LEVEL - 1) |
bb803951 CM |
294 | parent_buf = path->nodes[level + 1]; |
295 | pslot = path->slots[level + 1]; | |
296 | ||
297 | if (!parent_buf) { | |
234b63a0 | 298 | struct btrfs_buffer *child; |
bb803951 CM |
299 | u64 blocknr = mid_buf->blocknr; |
300 | ||
7518a238 | 301 | if (btrfs_header_nritems(&mid->header) != 1) |
bb803951 CM |
302 | return 0; |
303 | ||
304 | /* promote the child to a root */ | |
305 | child = read_node_slot(root, mid_buf, 0); | |
306 | BUG_ON(!child); | |
307 | root->node = child; | |
308 | path->nodes[level] = NULL; | |
309 | /* once for the path */ | |
234b63a0 | 310 | btrfs_block_release(root, mid_buf); |
bb803951 | 311 | /* once for the root ptr */ |
234b63a0 | 312 | btrfs_block_release(root, mid_buf); |
ed2ff2cb | 313 | clean_tree_block(root, mid_buf); |
234b63a0 | 314 | return btrfs_free_extent(root, blocknr, 1); |
bb803951 CM |
315 | } |
316 | parent = &parent_buf->node; | |
317 | ||
123abc88 CM |
318 | if (btrfs_header_nritems(&mid->header) > |
319 | BTRFS_NODEPTRS_PER_BLOCK(root) / 4) | |
bb803951 CM |
320 | return 0; |
321 | ||
bb803951 CM |
322 | left_buf = read_node_slot(root, parent_buf, pslot - 1); |
323 | right_buf = read_node_slot(root, parent_buf, pslot + 1); | |
79f95c82 CM |
324 | |
325 | /* first, try to make some room in the middle buffer */ | |
bb803951 | 326 | if (left_buf) { |
02217ed2 CM |
327 | btrfs_cow_block(root, left_buf, parent_buf, |
328 | pslot - 1, &left_buf); | |
bb803951 | 329 | left = &left_buf->node; |
7518a238 | 330 | orig_slot += btrfs_header_nritems(&left->header); |
79f95c82 CM |
331 | wret = push_node_left(root, left_buf, mid_buf); |
332 | if (wret < 0) | |
333 | ret = wret; | |
bb803951 | 334 | } |
79f95c82 CM |
335 | |
336 | /* | |
337 | * then try to empty the right most buffer into the middle | |
338 | */ | |
bb803951 | 339 | if (right_buf) { |
02217ed2 CM |
340 | btrfs_cow_block(root, right_buf, parent_buf, |
341 | pslot + 1, &right_buf); | |
79f95c82 CM |
342 | right = &right_buf->node; |
343 | wret = push_node_left(root, mid_buf, right_buf); | |
344 | if (wret < 0) | |
345 | ret = wret; | |
7518a238 | 346 | if (btrfs_header_nritems(&right->header) == 0) { |
bb803951 | 347 | u64 blocknr = right_buf->blocknr; |
234b63a0 | 348 | btrfs_block_release(root, right_buf); |
ed2ff2cb | 349 | clean_tree_block(root, right_buf); |
bb803951 CM |
350 | right_buf = NULL; |
351 | right = NULL; | |
352 | wret = del_ptr(root, path, level + 1, pslot + 1); | |
353 | if (wret) | |
354 | ret = wret; | |
234b63a0 | 355 | wret = btrfs_free_extent(root, blocknr, 1); |
bb803951 CM |
356 | if (wret) |
357 | ret = wret; | |
358 | } else { | |
123abc88 CM |
359 | memcpy(&parent->ptrs[pslot + 1].key, |
360 | &right->ptrs[0].key, | |
e2fa7227 | 361 | sizeof(struct btrfs_disk_key)); |
02217ed2 | 362 | BUG_ON(list_empty(&parent_buf->dirty)); |
bb803951 CM |
363 | } |
364 | } | |
7518a238 | 365 | if (btrfs_header_nritems(&mid->header) == 1) { |
79f95c82 CM |
366 | /* |
367 | * we're not allowed to leave a node with one item in the | |
368 | * tree during a delete. A deletion from lower in the tree | |
369 | * could try to delete the only pointer in this node. | |
370 | * So, pull some keys from the left. | |
371 | * There has to be a left pointer at this point because | |
372 | * otherwise we would have pulled some pointers from the | |
373 | * right | |
374 | */ | |
375 | BUG_ON(!left_buf); | |
376 | wret = balance_node_right(root, mid_buf, left_buf); | |
377 | if (wret < 0) | |
378 | ret = wret; | |
379 | BUG_ON(wret == 1); | |
380 | } | |
7518a238 | 381 | if (btrfs_header_nritems(&mid->header) == 0) { |
79f95c82 | 382 | /* we've managed to empty the middle node, drop it */ |
bb803951 | 383 | u64 blocknr = mid_buf->blocknr; |
234b63a0 | 384 | btrfs_block_release(root, mid_buf); |
ed2ff2cb | 385 | clean_tree_block(root, mid_buf); |
bb803951 CM |
386 | mid_buf = NULL; |
387 | mid = NULL; | |
388 | wret = del_ptr(root, path, level + 1, pslot); | |
389 | if (wret) | |
390 | ret = wret; | |
234b63a0 | 391 | wret = btrfs_free_extent(root, blocknr, 1); |
bb803951 CM |
392 | if (wret) |
393 | ret = wret; | |
79f95c82 CM |
394 | } else { |
395 | /* update the parent key to reflect our changes */ | |
123abc88 | 396 | memcpy(&parent->ptrs[pslot].key, &mid->ptrs[0].key, |
e2fa7227 | 397 | sizeof(struct btrfs_disk_key)); |
02217ed2 | 398 | BUG_ON(list_empty(&parent_buf->dirty)); |
79f95c82 | 399 | } |
bb803951 | 400 | |
79f95c82 | 401 | /* update the path */ |
bb803951 | 402 | if (left_buf) { |
7518a238 | 403 | if (btrfs_header_nritems(&left->header) > orig_slot) { |
bb803951 CM |
404 | left_buf->count++; // released below |
405 | path->nodes[level] = left_buf; | |
406 | path->slots[level + 1] -= 1; | |
407 | path->slots[level] = orig_slot; | |
408 | if (mid_buf) | |
234b63a0 | 409 | btrfs_block_release(root, mid_buf); |
bb803951 | 410 | } else { |
7518a238 | 411 | orig_slot -= btrfs_header_nritems(&left->header); |
bb803951 CM |
412 | path->slots[level] = orig_slot; |
413 | } | |
414 | } | |
79f95c82 | 415 | /* double check we haven't messed things up */ |
123abc88 | 416 | check_block(root, path, level); |
1d4f8a0c CM |
417 | if (orig_ptr != btrfs_node_blockptr(&path->nodes[level]->node, |
418 | path->slots[level])) | |
79f95c82 | 419 | BUG(); |
bb803951 CM |
420 | |
421 | if (right_buf) | |
234b63a0 | 422 | btrfs_block_release(root, right_buf); |
bb803951 | 423 | if (left_buf) |
234b63a0 | 424 | btrfs_block_release(root, left_buf); |
bb803951 CM |
425 | return ret; |
426 | } | |
427 | ||
74123bd7 CM |
428 | /* |
429 | * look for key in the tree. path is filled in with nodes along the way | |
430 | * if key is found, we return zero and you can find the item in the leaf | |
431 | * level of the path (level 0) | |
432 | * | |
433 | * If the key isn't found, the path points to the slot where it should | |
aa5d6bed CM |
434 | * be inserted, and 1 is returned. If there are other errors during the |
435 | * search a negative error number is returned. | |
97571fd0 CM |
436 | * |
437 | * if ins_len > 0, nodes and leaves will be split as we walk down the | |
438 | * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if | |
439 | * possible) | |
74123bd7 | 440 | */ |
234b63a0 CM |
441 | int btrfs_search_slot(struct btrfs_root *root, struct btrfs_key *key, |
442 | struct btrfs_path *p, int ins_len, int cow) | |
be0e5c09 | 443 | { |
234b63a0 CM |
444 | struct btrfs_buffer *b; |
445 | struct btrfs_buffer *cow_buf; | |
446 | struct btrfs_node *c; | |
be0e5c09 CM |
447 | int slot; |
448 | int ret; | |
449 | int level; | |
5c680ed6 | 450 | |
bb803951 CM |
451 | again: |
452 | b = root->node; | |
eb60ceac CM |
453 | b->count++; |
454 | while (b) { | |
7518a238 | 455 | level = btrfs_header_level(&b->node.header); |
02217ed2 CM |
456 | if (cow) { |
457 | int wret; | |
458 | wret = btrfs_cow_block(root, b, p->nodes[level + 1], | |
459 | p->slots[level + 1], &cow_buf); | |
460 | b = cow_buf; | |
461 | } | |
462 | BUG_ON(!cow && ins_len); | |
eb60ceac | 463 | c = &b->node; |
eb60ceac | 464 | p->nodes[level] = b; |
123abc88 | 465 | ret = check_block(root, p, level); |
aa5d6bed CM |
466 | if (ret) |
467 | return -1; | |
be0e5c09 | 468 | ret = bin_search(c, key, &slot); |
7518a238 | 469 | if (!btrfs_is_leaf(c)) { |
be0e5c09 CM |
470 | if (ret && slot > 0) |
471 | slot -= 1; | |
472 | p->slots[level] = slot; | |
7518a238 | 473 | if (ins_len > 0 && btrfs_header_nritems(&c->header) == |
123abc88 | 474 | BTRFS_NODEPTRS_PER_BLOCK(root)) { |
5c680ed6 CM |
475 | int sret = split_node(root, p, level); |
476 | BUG_ON(sret > 0); | |
477 | if (sret) | |
478 | return sret; | |
479 | b = p->nodes[level]; | |
480 | c = &b->node; | |
481 | slot = p->slots[level]; | |
bb803951 CM |
482 | } else if (ins_len < 0) { |
483 | int sret = balance_level(root, p, level); | |
484 | if (sret) | |
485 | return sret; | |
486 | b = p->nodes[level]; | |
487 | if (!b) | |
488 | goto again; | |
489 | c = &b->node; | |
490 | slot = p->slots[level]; | |
7518a238 | 491 | BUG_ON(btrfs_header_nritems(&c->header) == 1); |
5c680ed6 | 492 | } |
1d4f8a0c | 493 | b = read_tree_block(root, btrfs_node_blockptr(c, slot)); |
be0e5c09 | 494 | } else { |
234b63a0 | 495 | struct btrfs_leaf *l = (struct btrfs_leaf *)c; |
be0e5c09 | 496 | p->slots[level] = slot; |
123abc88 | 497 | if (ins_len > 0 && btrfs_leaf_free_space(root, l) < |
0783fcfc | 498 | sizeof(struct btrfs_item) + ins_len) { |
5c680ed6 CM |
499 | int sret = split_leaf(root, p, ins_len); |
500 | BUG_ON(sret > 0); | |
501 | if (sret) | |
502 | return sret; | |
503 | } | |
bb803951 | 504 | BUG_ON(root->node->count == 1); |
be0e5c09 CM |
505 | return ret; |
506 | } | |
507 | } | |
bb803951 | 508 | BUG_ON(root->node->count == 1); |
aa5d6bed | 509 | return 1; |
be0e5c09 CM |
510 | } |
511 | ||
74123bd7 CM |
512 | /* |
513 | * adjust the pointers going up the tree, starting at level | |
514 | * making sure the right key of each node is points to 'key'. | |
515 | * This is used after shifting pointers to the left, so it stops | |
516 | * fixing up pointers when a given leaf/node is not in slot 0 of the | |
517 | * higher levels | |
aa5d6bed CM |
518 | * |
519 | * If this fails to write a tree block, it returns -1, but continues | |
520 | * fixing up the blocks in ram so the tree is consistent. | |
74123bd7 | 521 | */ |
234b63a0 CM |
522 | static int fixup_low_keys(struct btrfs_root *root, |
523 | struct btrfs_path *path, struct btrfs_disk_key *key, | |
eb60ceac | 524 | int level) |
be0e5c09 CM |
525 | { |
526 | int i; | |
aa5d6bed | 527 | int ret = 0; |
234b63a0 CM |
528 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
529 | struct btrfs_node *t; | |
be0e5c09 | 530 | int tslot = path->slots[i]; |
eb60ceac | 531 | if (!path->nodes[i]) |
be0e5c09 | 532 | break; |
eb60ceac | 533 | t = &path->nodes[i]->node; |
123abc88 | 534 | memcpy(&t->ptrs[tslot].key, key, sizeof(*key)); |
02217ed2 | 535 | BUG_ON(list_empty(&path->nodes[i]->dirty)); |
be0e5c09 CM |
536 | if (tslot != 0) |
537 | break; | |
538 | } | |
aa5d6bed | 539 | return ret; |
be0e5c09 CM |
540 | } |
541 | ||
74123bd7 CM |
542 | /* |
543 | * try to push data from one node into the next node left in the | |
79f95c82 | 544 | * tree. |
aa5d6bed CM |
545 | * |
546 | * returns 0 if some ptrs were pushed left, < 0 if there was some horrible | |
547 | * error, and > 0 if there was no room in the left hand block. | |
74123bd7 | 548 | */ |
234b63a0 CM |
549 | static int push_node_left(struct btrfs_root *root, struct btrfs_buffer *dst_buf, |
550 | struct btrfs_buffer *src_buf) | |
be0e5c09 | 551 | { |
234b63a0 CM |
552 | struct btrfs_node *src = &src_buf->node; |
553 | struct btrfs_node *dst = &dst_buf->node; | |
be0e5c09 | 554 | int push_items = 0; |
bb803951 CM |
555 | int src_nritems; |
556 | int dst_nritems; | |
aa5d6bed | 557 | int ret = 0; |
be0e5c09 | 558 | |
7518a238 CM |
559 | src_nritems = btrfs_header_nritems(&src->header); |
560 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 561 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
eb60ceac | 562 | if (push_items <= 0) { |
be0e5c09 | 563 | return 1; |
eb60ceac | 564 | } |
be0e5c09 | 565 | |
bb803951 | 566 | if (src_nritems < push_items) |
79f95c82 CM |
567 | push_items = src_nritems; |
568 | ||
123abc88 CM |
569 | memcpy(dst->ptrs + dst_nritems, src->ptrs, |
570 | push_items * sizeof(struct btrfs_key_ptr)); | |
bb803951 | 571 | if (push_items < src_nritems) { |
123abc88 | 572 | memmove(src->ptrs, src->ptrs + push_items, |
e2fa7227 | 573 | (src_nritems - push_items) * |
123abc88 | 574 | sizeof(struct btrfs_key_ptr)); |
bb803951 | 575 | } |
7518a238 CM |
576 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
577 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
02217ed2 CM |
578 | BUG_ON(list_empty(&src_buf->dirty)); |
579 | BUG_ON(list_empty(&dst_buf->dirty)); | |
79f95c82 CM |
580 | return ret; |
581 | } | |
582 | ||
583 | /* | |
584 | * try to push data from one node into the next node right in the | |
585 | * tree. | |
586 | * | |
587 | * returns 0 if some ptrs were pushed, < 0 if there was some horrible | |
588 | * error, and > 0 if there was no room in the right hand block. | |
589 | * | |
590 | * this will only push up to 1/2 the contents of the left node over | |
591 | */ | |
234b63a0 CM |
592 | static int balance_node_right(struct btrfs_root *root, |
593 | struct btrfs_buffer *dst_buf, | |
594 | struct btrfs_buffer *src_buf) | |
79f95c82 | 595 | { |
234b63a0 CM |
596 | struct btrfs_node *src = &src_buf->node; |
597 | struct btrfs_node *dst = &dst_buf->node; | |
79f95c82 CM |
598 | int push_items = 0; |
599 | int max_push; | |
600 | int src_nritems; | |
601 | int dst_nritems; | |
602 | int ret = 0; | |
79f95c82 | 603 | |
7518a238 CM |
604 | src_nritems = btrfs_header_nritems(&src->header); |
605 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 606 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
79f95c82 CM |
607 | if (push_items <= 0) { |
608 | return 1; | |
609 | } | |
610 | ||
611 | max_push = src_nritems / 2 + 1; | |
612 | /* don't try to empty the node */ | |
613 | if (max_push > src_nritems) | |
614 | return 1; | |
615 | if (max_push < push_items) | |
616 | push_items = max_push; | |
617 | ||
123abc88 CM |
618 | memmove(dst->ptrs + push_items, dst->ptrs, |
619 | dst_nritems * sizeof(struct btrfs_key_ptr)); | |
620 | memcpy(dst->ptrs, src->ptrs + src_nritems - push_items, | |
621 | push_items * sizeof(struct btrfs_key_ptr)); | |
79f95c82 | 622 | |
7518a238 CM |
623 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
624 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
79f95c82 | 625 | |
02217ed2 CM |
626 | BUG_ON(list_empty(&src_buf->dirty)); |
627 | BUG_ON(list_empty(&dst_buf->dirty)); | |
aa5d6bed | 628 | return ret; |
be0e5c09 CM |
629 | } |
630 | ||
97571fd0 CM |
631 | /* |
632 | * helper function to insert a new root level in the tree. | |
633 | * A new node is allocated, and a single item is inserted to | |
634 | * point to the existing root | |
aa5d6bed CM |
635 | * |
636 | * returns zero on success or < 0 on failure. | |
97571fd0 | 637 | */ |
234b63a0 CM |
638 | static int insert_new_root(struct btrfs_root *root, |
639 | struct btrfs_path *path, int level) | |
5c680ed6 | 640 | { |
234b63a0 CM |
641 | struct btrfs_buffer *t; |
642 | struct btrfs_node *lower; | |
643 | struct btrfs_node *c; | |
e2fa7227 | 644 | struct btrfs_disk_key *lower_key; |
5c680ed6 CM |
645 | |
646 | BUG_ON(path->nodes[level]); | |
647 | BUG_ON(path->nodes[level-1] != root->node); | |
648 | ||
234b63a0 | 649 | t = btrfs_alloc_free_block(root); |
5c680ed6 | 650 | c = &t->node; |
123abc88 | 651 | memset(c, 0, root->blocksize); |
7518a238 CM |
652 | btrfs_set_header_nritems(&c->header, 1); |
653 | btrfs_set_header_level(&c->header, level); | |
654 | btrfs_set_header_blocknr(&c->header, t->blocknr); | |
655 | btrfs_set_header_parentid(&c->header, | |
656 | btrfs_header_parentid(&root->node->node.header)); | |
5c680ed6 | 657 | lower = &path->nodes[level-1]->node; |
7518a238 | 658 | if (btrfs_is_leaf(lower)) |
234b63a0 | 659 | lower_key = &((struct btrfs_leaf *)lower)->items[0].key; |
5c680ed6 | 660 | else |
123abc88 CM |
661 | lower_key = &lower->ptrs[0].key; |
662 | memcpy(&c->ptrs[0].key, lower_key, sizeof(struct btrfs_disk_key)); | |
1d4f8a0c | 663 | btrfs_set_node_blockptr(c, 0, path->nodes[level - 1]->blocknr); |
5c680ed6 | 664 | /* the super has an extra ref to root->node */ |
234b63a0 | 665 | btrfs_block_release(root, root->node); |
5c680ed6 CM |
666 | root->node = t; |
667 | t->count++; | |
5c680ed6 CM |
668 | path->nodes[level] = t; |
669 | path->slots[level] = 0; | |
670 | return 0; | |
671 | } | |
672 | ||
74123bd7 CM |
673 | /* |
674 | * worker function to insert a single pointer in a node. | |
675 | * the node should have enough room for the pointer already | |
97571fd0 | 676 | * |
74123bd7 CM |
677 | * slot and level indicate where you want the key to go, and |
678 | * blocknr is the block the key points to. | |
aa5d6bed CM |
679 | * |
680 | * returns zero on success and < 0 on any error | |
74123bd7 | 681 | */ |
234b63a0 CM |
682 | static int insert_ptr(struct btrfs_root *root, |
683 | struct btrfs_path *path, struct btrfs_disk_key *key, | |
74123bd7 CM |
684 | u64 blocknr, int slot, int level) |
685 | { | |
234b63a0 | 686 | struct btrfs_node *lower; |
74123bd7 | 687 | int nritems; |
5c680ed6 CM |
688 | |
689 | BUG_ON(!path->nodes[level]); | |
74123bd7 | 690 | lower = &path->nodes[level]->node; |
7518a238 | 691 | nritems = btrfs_header_nritems(&lower->header); |
74123bd7 CM |
692 | if (slot > nritems) |
693 | BUG(); | |
123abc88 | 694 | if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root)) |
74123bd7 CM |
695 | BUG(); |
696 | if (slot != nritems) { | |
123abc88 CM |
697 | memmove(lower->ptrs + slot + 1, lower->ptrs + slot, |
698 | (nritems - slot) * sizeof(struct btrfs_key_ptr)); | |
74123bd7 | 699 | } |
123abc88 | 700 | memcpy(&lower->ptrs[slot].key, key, sizeof(struct btrfs_disk_key)); |
1d4f8a0c | 701 | btrfs_set_node_blockptr(lower, slot, blocknr); |
7518a238 | 702 | btrfs_set_header_nritems(&lower->header, nritems + 1); |
02217ed2 | 703 | BUG_ON(list_empty(&path->nodes[level]->dirty)); |
74123bd7 CM |
704 | return 0; |
705 | } | |
706 | ||
97571fd0 CM |
707 | /* |
708 | * split the node at the specified level in path in two. | |
709 | * The path is corrected to point to the appropriate node after the split | |
710 | * | |
711 | * Before splitting this tries to make some room in the node by pushing | |
712 | * left and right, if either one works, it returns right away. | |
aa5d6bed CM |
713 | * |
714 | * returns 0 on success and < 0 on failure | |
97571fd0 | 715 | */ |
234b63a0 | 716 | static int split_node(struct btrfs_root *root, struct btrfs_path *path, |
aa5d6bed | 717 | int level) |
be0e5c09 | 718 | { |
234b63a0 CM |
719 | struct btrfs_buffer *t; |
720 | struct btrfs_node *c; | |
721 | struct btrfs_buffer *split_buffer; | |
722 | struct btrfs_node *split; | |
be0e5c09 | 723 | int mid; |
5c680ed6 | 724 | int ret; |
aa5d6bed | 725 | int wret; |
7518a238 | 726 | u32 c_nritems; |
eb60ceac | 727 | |
5c680ed6 CM |
728 | t = path->nodes[level]; |
729 | c = &t->node; | |
730 | if (t == root->node) { | |
731 | /* trying to split the root, lets make a new one */ | |
732 | ret = insert_new_root(root, path, level + 1); | |
733 | if (ret) | |
734 | return ret; | |
be0e5c09 | 735 | } |
7518a238 | 736 | c_nritems = btrfs_header_nritems(&c->header); |
234b63a0 | 737 | split_buffer = btrfs_alloc_free_block(root); |
5c680ed6 | 738 | split = &split_buffer->node; |
7518a238 CM |
739 | btrfs_set_header_flags(&split->header, btrfs_header_flags(&c->header)); |
740 | btrfs_set_header_blocknr(&split->header, split_buffer->blocknr); | |
741 | btrfs_set_header_parentid(&split->header, | |
742 | btrfs_header_parentid(&root->node->node.header)); | |
743 | mid = (c_nritems + 1) / 2; | |
123abc88 CM |
744 | memcpy(split->ptrs, c->ptrs + mid, |
745 | (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); | |
7518a238 CM |
746 | btrfs_set_header_nritems(&split->header, c_nritems - mid); |
747 | btrfs_set_header_nritems(&c->header, mid); | |
aa5d6bed CM |
748 | ret = 0; |
749 | ||
02217ed2 | 750 | BUG_ON(list_empty(&t->dirty)); |
123abc88 CM |
751 | wret = insert_ptr(root, path, &split->ptrs[0].key, |
752 | split_buffer->blocknr, path->slots[level + 1] + 1, | |
753 | level + 1); | |
aa5d6bed CM |
754 | if (wret) |
755 | ret = wret; | |
756 | ||
5de08d7d | 757 | if (path->slots[level] >= mid) { |
5c680ed6 | 758 | path->slots[level] -= mid; |
234b63a0 | 759 | btrfs_block_release(root, t); |
5c680ed6 CM |
760 | path->nodes[level] = split_buffer; |
761 | path->slots[level + 1] += 1; | |
762 | } else { | |
234b63a0 | 763 | btrfs_block_release(root, split_buffer); |
be0e5c09 | 764 | } |
aa5d6bed | 765 | return ret; |
be0e5c09 CM |
766 | } |
767 | ||
74123bd7 CM |
768 | /* |
769 | * how many bytes are required to store the items in a leaf. start | |
770 | * and nr indicate which items in the leaf to check. This totals up the | |
771 | * space used both by the item structs and the item data | |
772 | */ | |
234b63a0 | 773 | static int leaf_space_used(struct btrfs_leaf *l, int start, int nr) |
be0e5c09 CM |
774 | { |
775 | int data_len; | |
776 | int end = start + nr - 1; | |
777 | ||
778 | if (!nr) | |
779 | return 0; | |
0783fcfc CM |
780 | data_len = btrfs_item_end(l->items + start); |
781 | data_len = data_len - btrfs_item_offset(l->items + end); | |
782 | data_len += sizeof(struct btrfs_item) * nr; | |
be0e5c09 CM |
783 | return data_len; |
784 | } | |
785 | ||
00ec4c51 CM |
786 | /* |
787 | * push some data in the path leaf to the right, trying to free up at | |
788 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
aa5d6bed CM |
789 | * |
790 | * returns 1 if the push failed because the other node didn't have enough | |
791 | * room, 0 if everything worked out and < 0 if there were major errors. | |
00ec4c51 | 792 | */ |
234b63a0 | 793 | static int push_leaf_right(struct btrfs_root *root, struct btrfs_path *path, |
aa5d6bed | 794 | int data_size) |
00ec4c51 | 795 | { |
234b63a0 CM |
796 | struct btrfs_buffer *left_buf = path->nodes[0]; |
797 | struct btrfs_leaf *left = &left_buf->leaf; | |
798 | struct btrfs_leaf *right; | |
799 | struct btrfs_buffer *right_buf; | |
800 | struct btrfs_buffer *upper; | |
00ec4c51 CM |
801 | int slot; |
802 | int i; | |
803 | int free_space; | |
804 | int push_space = 0; | |
805 | int push_items = 0; | |
0783fcfc | 806 | struct btrfs_item *item; |
7518a238 CM |
807 | u32 left_nritems; |
808 | u32 right_nritems; | |
00ec4c51 CM |
809 | |
810 | slot = path->slots[1]; | |
811 | if (!path->nodes[1]) { | |
812 | return 1; | |
813 | } | |
814 | upper = path->nodes[1]; | |
7518a238 | 815 | if (slot >= btrfs_header_nritems(&upper->node.header) - 1) { |
00ec4c51 CM |
816 | return 1; |
817 | } | |
1d4f8a0c CM |
818 | right_buf = read_tree_block(root, btrfs_node_blockptr(&upper->node, |
819 | slot + 1)); | |
00ec4c51 | 820 | right = &right_buf->leaf; |
123abc88 | 821 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 822 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 823 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
824 | return 1; |
825 | } | |
02217ed2 CM |
826 | /* cow and double check */ |
827 | btrfs_cow_block(root, right_buf, upper, slot + 1, &right_buf); | |
828 | right = &right_buf->leaf; | |
123abc88 | 829 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 830 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 831 | btrfs_block_release(root, right_buf); |
02217ed2 CM |
832 | return 1; |
833 | } | |
834 | ||
7518a238 CM |
835 | left_nritems = btrfs_header_nritems(&left->header); |
836 | for (i = left_nritems - 1; i >= 0; i--) { | |
00ec4c51 CM |
837 | item = left->items + i; |
838 | if (path->slots[0] == i) | |
839 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
840 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
841 | free_space) | |
00ec4c51 CM |
842 | break; |
843 | push_items++; | |
0783fcfc | 844 | push_space += btrfs_item_size(item) + sizeof(*item); |
00ec4c51 CM |
845 | } |
846 | if (push_items == 0) { | |
234b63a0 | 847 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
848 | return 1; |
849 | } | |
7518a238 | 850 | right_nritems = btrfs_header_nritems(&right->header); |
00ec4c51 | 851 | /* push left to right */ |
0783fcfc | 852 | push_space = btrfs_item_end(left->items + left_nritems - push_items); |
123abc88 | 853 | push_space -= leaf_data_end(root, left); |
00ec4c51 | 854 | /* make room in the right data area */ |
123abc88 CM |
855 | memmove(btrfs_leaf_data(right) + leaf_data_end(root, right) - |
856 | push_space, btrfs_leaf_data(right) + leaf_data_end(root, right), | |
857 | BTRFS_LEAF_DATA_SIZE(root) - leaf_data_end(root, right)); | |
00ec4c51 | 858 | /* copy from the left data area */ |
123abc88 CM |
859 | memcpy(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - push_space, |
860 | btrfs_leaf_data(left) + leaf_data_end(root, left), push_space); | |
00ec4c51 | 861 | memmove(right->items + push_items, right->items, |
0783fcfc | 862 | right_nritems * sizeof(struct btrfs_item)); |
00ec4c51 | 863 | /* copy the items from left to right */ |
7518a238 | 864 | memcpy(right->items, left->items + left_nritems - push_items, |
0783fcfc | 865 | push_items * sizeof(struct btrfs_item)); |
00ec4c51 CM |
866 | |
867 | /* update the item pointers */ | |
7518a238 CM |
868 | right_nritems += push_items; |
869 | btrfs_set_header_nritems(&right->header, right_nritems); | |
123abc88 | 870 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
7518a238 | 871 | for (i = 0; i < right_nritems; i++) { |
0783fcfc CM |
872 | btrfs_set_item_offset(right->items + i, push_space - |
873 | btrfs_item_size(right->items + i)); | |
874 | push_space = btrfs_item_offset(right->items + i); | |
00ec4c51 | 875 | } |
7518a238 CM |
876 | left_nritems -= push_items; |
877 | btrfs_set_header_nritems(&left->header, left_nritems); | |
00ec4c51 | 878 | |
02217ed2 CM |
879 | BUG_ON(list_empty(&left_buf->dirty)); |
880 | BUG_ON(list_empty(&right_buf->dirty)); | |
123abc88 | 881 | memcpy(&upper->node.ptrs[slot + 1].key, |
e2fa7227 | 882 | &right->items[0].key, sizeof(struct btrfs_disk_key)); |
02217ed2 CM |
883 | BUG_ON(list_empty(&upper->dirty)); |
884 | ||
00ec4c51 | 885 | /* then fixup the leaf pointer in the path */ |
7518a238 CM |
886 | if (path->slots[0] >= left_nritems) { |
887 | path->slots[0] -= left_nritems; | |
234b63a0 | 888 | btrfs_block_release(root, path->nodes[0]); |
00ec4c51 CM |
889 | path->nodes[0] = right_buf; |
890 | path->slots[1] += 1; | |
891 | } else { | |
234b63a0 | 892 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
893 | } |
894 | return 0; | |
895 | } | |
74123bd7 CM |
896 | /* |
897 | * push some data in the path leaf to the left, trying to free up at | |
898 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
899 | */ | |
234b63a0 | 900 | static int push_leaf_left(struct btrfs_root *root, struct btrfs_path *path, |
aa5d6bed | 901 | int data_size) |
be0e5c09 | 902 | { |
234b63a0 CM |
903 | struct btrfs_buffer *right_buf = path->nodes[0]; |
904 | struct btrfs_leaf *right = &right_buf->leaf; | |
905 | struct btrfs_buffer *t; | |
906 | struct btrfs_leaf *left; | |
be0e5c09 CM |
907 | int slot; |
908 | int i; | |
909 | int free_space; | |
910 | int push_space = 0; | |
911 | int push_items = 0; | |
0783fcfc | 912 | struct btrfs_item *item; |
7518a238 | 913 | u32 old_left_nritems; |
aa5d6bed CM |
914 | int ret = 0; |
915 | int wret; | |
be0e5c09 CM |
916 | |
917 | slot = path->slots[1]; | |
918 | if (slot == 0) { | |
919 | return 1; | |
920 | } | |
921 | if (!path->nodes[1]) { | |
922 | return 1; | |
923 | } | |
1d4f8a0c CM |
924 | t = read_tree_block(root, btrfs_node_blockptr(&path->nodes[1]->node, |
925 | slot - 1)); | |
eb60ceac | 926 | left = &t->leaf; |
123abc88 | 927 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 928 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 929 | btrfs_block_release(root, t); |
be0e5c09 CM |
930 | return 1; |
931 | } | |
02217ed2 CM |
932 | |
933 | /* cow and double check */ | |
934 | btrfs_cow_block(root, t, path->nodes[1], slot - 1, &t); | |
935 | left = &t->leaf; | |
123abc88 | 936 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 937 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 938 | btrfs_block_release(root, t); |
02217ed2 CM |
939 | return 1; |
940 | } | |
941 | ||
7518a238 | 942 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
be0e5c09 CM |
943 | item = right->items + i; |
944 | if (path->slots[0] == i) | |
945 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
946 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
947 | free_space) | |
be0e5c09 CM |
948 | break; |
949 | push_items++; | |
0783fcfc | 950 | push_space += btrfs_item_size(item) + sizeof(*item); |
be0e5c09 CM |
951 | } |
952 | if (push_items == 0) { | |
234b63a0 | 953 | btrfs_block_release(root, t); |
be0e5c09 CM |
954 | return 1; |
955 | } | |
956 | /* push data from right to left */ | |
7518a238 | 957 | memcpy(left->items + btrfs_header_nritems(&left->header), |
0783fcfc | 958 | right->items, push_items * sizeof(struct btrfs_item)); |
123abc88 | 959 | push_space = BTRFS_LEAF_DATA_SIZE(root) - |
0783fcfc | 960 | btrfs_item_offset(right->items + push_items -1); |
123abc88 CM |
961 | memcpy(btrfs_leaf_data(left) + leaf_data_end(root, left) - push_space, |
962 | btrfs_leaf_data(right) + | |
963 | btrfs_item_offset(right->items + push_items - 1), | |
be0e5c09 | 964 | push_space); |
7518a238 | 965 | old_left_nritems = btrfs_header_nritems(&left->header); |
eb60ceac CM |
966 | BUG_ON(old_left_nritems < 0); |
967 | ||
0783fcfc | 968 | for (i = old_left_nritems; i < old_left_nritems + push_items; i++) { |
123abc88 CM |
969 | u32 ioff = btrfs_item_offset(left->items + i); |
970 | btrfs_set_item_offset(left->items + i, ioff - | |
971 | (BTRFS_LEAF_DATA_SIZE(root) - | |
0783fcfc CM |
972 | btrfs_item_offset(left->items + |
973 | old_left_nritems - 1))); | |
be0e5c09 | 974 | } |
7518a238 | 975 | btrfs_set_header_nritems(&left->header, old_left_nritems + push_items); |
be0e5c09 CM |
976 | |
977 | /* fixup right node */ | |
0783fcfc | 978 | push_space = btrfs_item_offset(right->items + push_items - 1) - |
123abc88 CM |
979 | leaf_data_end(root, right); |
980 | memmove(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - | |
981 | push_space, btrfs_leaf_data(right) + | |
982 | leaf_data_end(root, right), push_space); | |
be0e5c09 | 983 | memmove(right->items, right->items + push_items, |
7518a238 | 984 | (btrfs_header_nritems(&right->header) - push_items) * |
0783fcfc | 985 | sizeof(struct btrfs_item)); |
7518a238 CM |
986 | btrfs_set_header_nritems(&right->header, |
987 | btrfs_header_nritems(&right->header) - | |
988 | push_items); | |
123abc88 | 989 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
eb60ceac | 990 | |
7518a238 | 991 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
0783fcfc CM |
992 | btrfs_set_item_offset(right->items + i, push_space - |
993 | btrfs_item_size(right->items + i)); | |
994 | push_space = btrfs_item_offset(right->items + i); | |
be0e5c09 | 995 | } |
eb60ceac | 996 | |
02217ed2 CM |
997 | BUG_ON(list_empty(&t->dirty)); |
998 | BUG_ON(list_empty(&right_buf->dirty)); | |
eb60ceac | 999 | |
aa5d6bed CM |
1000 | wret = fixup_low_keys(root, path, &right->items[0].key, 1); |
1001 | if (wret) | |
1002 | ret = wret; | |
be0e5c09 CM |
1003 | |
1004 | /* then fixup the leaf pointer in the path */ | |
1005 | if (path->slots[0] < push_items) { | |
1006 | path->slots[0] += old_left_nritems; | |
234b63a0 | 1007 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1008 | path->nodes[0] = t; |
be0e5c09 CM |
1009 | path->slots[1] -= 1; |
1010 | } else { | |
234b63a0 | 1011 | btrfs_block_release(root, t); |
be0e5c09 CM |
1012 | path->slots[0] -= push_items; |
1013 | } | |
eb60ceac | 1014 | BUG_ON(path->slots[0] < 0); |
aa5d6bed | 1015 | return ret; |
be0e5c09 CM |
1016 | } |
1017 | ||
74123bd7 CM |
1018 | /* |
1019 | * split the path's leaf in two, making sure there is at least data_size | |
1020 | * available for the resulting leaf level of the path. | |
aa5d6bed CM |
1021 | * |
1022 | * returns 0 if all went well and < 0 on failure. | |
74123bd7 | 1023 | */ |
234b63a0 | 1024 | static int split_leaf(struct btrfs_root *root, struct btrfs_path *path, |
aa5d6bed | 1025 | int data_size) |
be0e5c09 | 1026 | { |
234b63a0 CM |
1027 | struct btrfs_buffer *l_buf; |
1028 | struct btrfs_leaf *l; | |
7518a238 | 1029 | u32 nritems; |
eb60ceac CM |
1030 | int mid; |
1031 | int slot; | |
234b63a0 CM |
1032 | struct btrfs_leaf *right; |
1033 | struct btrfs_buffer *right_buffer; | |
0783fcfc | 1034 | int space_needed = data_size + sizeof(struct btrfs_item); |
be0e5c09 CM |
1035 | int data_copy_size; |
1036 | int rt_data_off; | |
1037 | int i; | |
1038 | int ret; | |
aa5d6bed CM |
1039 | int wret; |
1040 | ||
eaee50e8 CM |
1041 | wret = push_leaf_left(root, path, data_size); |
1042 | if (wret < 0) | |
1043 | return wret; | |
1044 | if (wret) { | |
1045 | wret = push_leaf_right(root, path, data_size); | |
1046 | if (wret < 0) | |
1047 | return wret; | |
1048 | } | |
aa5d6bed CM |
1049 | l_buf = path->nodes[0]; |
1050 | l = &l_buf->leaf; | |
1051 | ||
1052 | /* did the pushes work? */ | |
123abc88 CM |
1053 | if (btrfs_leaf_free_space(root, l) >= |
1054 | sizeof(struct btrfs_item) + data_size) | |
aa5d6bed CM |
1055 | return 0; |
1056 | ||
5c680ed6 CM |
1057 | if (!path->nodes[1]) { |
1058 | ret = insert_new_root(root, path, 1); | |
1059 | if (ret) | |
1060 | return ret; | |
1061 | } | |
eb60ceac | 1062 | slot = path->slots[0]; |
7518a238 | 1063 | nritems = btrfs_header_nritems(&l->header); |
eb60ceac | 1064 | mid = (nritems + 1)/ 2; |
234b63a0 | 1065 | right_buffer = btrfs_alloc_free_block(root); |
eb60ceac CM |
1066 | BUG_ON(!right_buffer); |
1067 | BUG_ON(mid == nritems); | |
1068 | right = &right_buffer->leaf; | |
123abc88 | 1069 | memset(&right->header, 0, sizeof(right->header)); |
be0e5c09 | 1070 | if (mid <= slot) { |
97571fd0 | 1071 | /* FIXME, just alloc a new leaf here */ |
be0e5c09 | 1072 | if (leaf_space_used(l, mid, nritems - mid) + space_needed > |
123abc88 | 1073 | BTRFS_LEAF_DATA_SIZE(root)) |
be0e5c09 CM |
1074 | BUG(); |
1075 | } else { | |
97571fd0 | 1076 | /* FIXME, just alloc a new leaf here */ |
be0e5c09 | 1077 | if (leaf_space_used(l, 0, mid + 1) + space_needed > |
123abc88 | 1078 | BTRFS_LEAF_DATA_SIZE(root)) |
be0e5c09 CM |
1079 | BUG(); |
1080 | } | |
7518a238 CM |
1081 | btrfs_set_header_nritems(&right->header, nritems - mid); |
1082 | btrfs_set_header_blocknr(&right->header, right_buffer->blocknr); | |
1083 | btrfs_set_header_level(&right->header, 0); | |
1084 | btrfs_set_header_parentid(&right->header, | |
1085 | btrfs_header_parentid(&root->node->node.header)); | |
123abc88 CM |
1086 | data_copy_size = btrfs_item_end(l->items + mid) - |
1087 | leaf_data_end(root, l); | |
be0e5c09 | 1088 | memcpy(right->items, l->items + mid, |
0783fcfc | 1089 | (nritems - mid) * sizeof(struct btrfs_item)); |
123abc88 CM |
1090 | memcpy(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - |
1091 | data_copy_size, btrfs_leaf_data(l) + | |
1092 | leaf_data_end(root, l), data_copy_size); | |
1093 | rt_data_off = BTRFS_LEAF_DATA_SIZE(root) - | |
1094 | btrfs_item_end(l->items + mid); | |
74123bd7 | 1095 | |
0783fcfc | 1096 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
123abc88 | 1097 | u32 ioff = btrfs_item_offset(right->items + i); |
0783fcfc CM |
1098 | btrfs_set_item_offset(right->items + i, ioff + rt_data_off); |
1099 | } | |
74123bd7 | 1100 | |
7518a238 | 1101 | btrfs_set_header_nritems(&l->header, mid); |
aa5d6bed CM |
1102 | ret = 0; |
1103 | wret = insert_ptr(root, path, &right->items[0].key, | |
5c680ed6 | 1104 | right_buffer->blocknr, path->slots[1] + 1, 1); |
aa5d6bed CM |
1105 | if (wret) |
1106 | ret = wret; | |
02217ed2 CM |
1107 | BUG_ON(list_empty(&right_buffer->dirty)); |
1108 | BUG_ON(list_empty(&l_buf->dirty)); | |
eb60ceac | 1109 | BUG_ON(path->slots[0] != slot); |
be0e5c09 | 1110 | if (mid <= slot) { |
234b63a0 | 1111 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1112 | path->nodes[0] = right_buffer; |
be0e5c09 CM |
1113 | path->slots[0] -= mid; |
1114 | path->slots[1] += 1; | |
eb60ceac | 1115 | } else |
234b63a0 | 1116 | btrfs_block_release(root, right_buffer); |
eb60ceac | 1117 | BUG_ON(path->slots[0] < 0); |
be0e5c09 CM |
1118 | return ret; |
1119 | } | |
1120 | ||
74123bd7 CM |
1121 | /* |
1122 | * Given a key and some data, insert an item into the tree. | |
1123 | * This does all the path init required, making room in the tree if needed. | |
1124 | */ | |
62e2749e CM |
1125 | int btrfs_insert_empty_item(struct btrfs_root *root, struct btrfs_path *path, |
1126 | struct btrfs_key *cpu_key, u32 data_size) | |
be0e5c09 | 1127 | { |
aa5d6bed | 1128 | int ret = 0; |
be0e5c09 | 1129 | int slot; |
eb60ceac | 1130 | int slot_orig; |
234b63a0 CM |
1131 | struct btrfs_leaf *leaf; |
1132 | struct btrfs_buffer *leaf_buf; | |
7518a238 | 1133 | u32 nritems; |
be0e5c09 | 1134 | unsigned int data_end; |
e2fa7227 CM |
1135 | struct btrfs_disk_key disk_key; |
1136 | ||
1137 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); | |
be0e5c09 | 1138 | |
74123bd7 | 1139 | /* create a root if there isn't one */ |
5c680ed6 | 1140 | if (!root->node) |
cfaa7295 | 1141 | BUG(); |
62e2749e | 1142 | ret = btrfs_search_slot(root, cpu_key, path, data_size, 1); |
eb60ceac | 1143 | if (ret == 0) { |
62e2749e | 1144 | btrfs_release_path(root, path); |
f0930a37 | 1145 | return -EEXIST; |
aa5d6bed | 1146 | } |
ed2ff2cb CM |
1147 | if (ret < 0) |
1148 | goto out; | |
be0e5c09 | 1149 | |
62e2749e CM |
1150 | slot_orig = path->slots[0]; |
1151 | leaf_buf = path->nodes[0]; | |
eb60ceac | 1152 | leaf = &leaf_buf->leaf; |
74123bd7 | 1153 | |
7518a238 | 1154 | nritems = btrfs_header_nritems(&leaf->header); |
123abc88 | 1155 | data_end = leaf_data_end(root, leaf); |
eb60ceac | 1156 | |
123abc88 | 1157 | if (btrfs_leaf_free_space(root, leaf) < |
234b63a0 | 1158 | sizeof(struct btrfs_item) + data_size) |
be0e5c09 CM |
1159 | BUG(); |
1160 | ||
62e2749e | 1161 | slot = path->slots[0]; |
eb60ceac | 1162 | BUG_ON(slot < 0); |
be0e5c09 CM |
1163 | if (slot != nritems) { |
1164 | int i; | |
0783fcfc | 1165 | unsigned int old_data = btrfs_item_end(leaf->items + slot); |
be0e5c09 CM |
1166 | |
1167 | /* | |
1168 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1169 | */ | |
1170 | /* first correct the data pointers */ | |
0783fcfc | 1171 | for (i = slot; i < nritems; i++) { |
123abc88 | 1172 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
1173 | btrfs_set_item_offset(leaf->items + i, |
1174 | ioff - data_size); | |
1175 | } | |
be0e5c09 CM |
1176 | |
1177 | /* shift the items */ | |
1178 | memmove(leaf->items + slot + 1, leaf->items + slot, | |
0783fcfc | 1179 | (nritems - slot) * sizeof(struct btrfs_item)); |
be0e5c09 CM |
1180 | |
1181 | /* shift the data */ | |
123abc88 CM |
1182 | memmove(btrfs_leaf_data(leaf) + data_end - data_size, |
1183 | btrfs_leaf_data(leaf) + | |
be0e5c09 CM |
1184 | data_end, old_data - data_end); |
1185 | data_end = old_data; | |
1186 | } | |
62e2749e | 1187 | /* setup the item for the new data */ |
e2fa7227 CM |
1188 | memcpy(&leaf->items[slot].key, &disk_key, |
1189 | sizeof(struct btrfs_disk_key)); | |
0783fcfc CM |
1190 | btrfs_set_item_offset(leaf->items + slot, data_end - data_size); |
1191 | btrfs_set_item_size(leaf->items + slot, data_size); | |
7518a238 | 1192 | btrfs_set_header_nritems(&leaf->header, nritems + 1); |
aa5d6bed CM |
1193 | |
1194 | ret = 0; | |
8e19f2cd | 1195 | if (slot == 0) |
62e2749e | 1196 | ret = fixup_low_keys(root, path, &disk_key, 1); |
aa5d6bed | 1197 | |
02217ed2 | 1198 | BUG_ON(list_empty(&leaf_buf->dirty)); |
123abc88 | 1199 | if (btrfs_leaf_free_space(root, leaf) < 0) |
be0e5c09 | 1200 | BUG(); |
62e2749e | 1201 | check_leaf(root, path, 0); |
ed2ff2cb | 1202 | out: |
62e2749e CM |
1203 | return ret; |
1204 | } | |
1205 | ||
1206 | /* | |
1207 | * Given a key and some data, insert an item into the tree. | |
1208 | * This does all the path init required, making room in the tree if needed. | |
1209 | */ | |
1210 | int btrfs_insert_item(struct btrfs_root *root, struct btrfs_key *cpu_key, | |
1211 | void *data, u32 data_size) | |
1212 | { | |
1213 | int ret = 0; | |
1214 | struct btrfs_path path; | |
1215 | u8 *ptr; | |
1216 | ||
1217 | btrfs_init_path(&path); | |
1218 | ret = btrfs_insert_empty_item(root, &path, cpu_key, data_size); | |
1219 | if (!ret) { | |
1220 | ptr = btrfs_item_ptr(&path.nodes[0]->leaf, path.slots[0], u8); | |
1221 | memcpy(ptr, data, data_size); | |
1222 | } | |
234b63a0 | 1223 | btrfs_release_path(root, &path); |
aa5d6bed | 1224 | return ret; |
be0e5c09 CM |
1225 | } |
1226 | ||
74123bd7 | 1227 | /* |
5de08d7d | 1228 | * delete the pointer from a given node. |
74123bd7 CM |
1229 | * |
1230 | * If the delete empties a node, the node is removed from the tree, | |
1231 | * continuing all the way the root if required. The root is converted into | |
1232 | * a leaf if all the nodes are emptied. | |
1233 | */ | |
234b63a0 | 1234 | static int del_ptr(struct btrfs_root *root, struct btrfs_path *path, int level, |
bb803951 | 1235 | int slot) |
be0e5c09 | 1236 | { |
234b63a0 CM |
1237 | struct btrfs_node *node; |
1238 | struct btrfs_buffer *parent = path->nodes[level]; | |
7518a238 | 1239 | u32 nritems; |
aa5d6bed | 1240 | int ret = 0; |
bb803951 | 1241 | int wret; |
be0e5c09 | 1242 | |
bb803951 | 1243 | node = &parent->node; |
7518a238 | 1244 | nritems = btrfs_header_nritems(&node->header); |
bb803951 | 1245 | if (slot != nritems -1) { |
123abc88 CM |
1246 | memmove(node->ptrs + slot, node->ptrs + slot + 1, |
1247 | sizeof(struct btrfs_key_ptr) * (nritems - slot - 1)); | |
bb803951 | 1248 | } |
7518a238 CM |
1249 | nritems--; |
1250 | btrfs_set_header_nritems(&node->header, nritems); | |
1251 | if (nritems == 0 && parent == root->node) { | |
1252 | BUG_ON(btrfs_header_level(&root->node->node.header) != 1); | |
bb803951 | 1253 | /* just turn the root into a leaf and break */ |
7518a238 | 1254 | btrfs_set_header_level(&root->node->node.header, 0); |
bb803951 | 1255 | } else if (slot == 0) { |
123abc88 CM |
1256 | wret = fixup_low_keys(root, path, &node->ptrs[0].key, |
1257 | level + 1); | |
0f70abe2 CM |
1258 | if (wret) |
1259 | ret = wret; | |
be0e5c09 | 1260 | } |
02217ed2 | 1261 | BUG_ON(list_empty(&parent->dirty)); |
aa5d6bed | 1262 | return ret; |
be0e5c09 CM |
1263 | } |
1264 | ||
74123bd7 CM |
1265 | /* |
1266 | * delete the item at the leaf level in path. If that empties | |
1267 | * the leaf, remove it from the tree | |
1268 | */ | |
234b63a0 | 1269 | int btrfs_del_item(struct btrfs_root *root, struct btrfs_path *path) |
be0e5c09 | 1270 | { |
be0e5c09 | 1271 | int slot; |
234b63a0 CM |
1272 | struct btrfs_leaf *leaf; |
1273 | struct btrfs_buffer *leaf_buf; | |
be0e5c09 CM |
1274 | int doff; |
1275 | int dsize; | |
aa5d6bed CM |
1276 | int ret = 0; |
1277 | int wret; | |
7518a238 | 1278 | u32 nritems; |
be0e5c09 | 1279 | |
eb60ceac CM |
1280 | leaf_buf = path->nodes[0]; |
1281 | leaf = &leaf_buf->leaf; | |
4920c9ac | 1282 | slot = path->slots[0]; |
0783fcfc CM |
1283 | doff = btrfs_item_offset(leaf->items + slot); |
1284 | dsize = btrfs_item_size(leaf->items + slot); | |
7518a238 | 1285 | nritems = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 1286 | |
7518a238 | 1287 | if (slot != nritems - 1) { |
be0e5c09 | 1288 | int i; |
123abc88 CM |
1289 | int data_end = leaf_data_end(root, leaf); |
1290 | memmove(btrfs_leaf_data(leaf) + data_end + dsize, | |
1291 | btrfs_leaf_data(leaf) + data_end, | |
be0e5c09 | 1292 | doff - data_end); |
0783fcfc | 1293 | for (i = slot + 1; i < nritems; i++) { |
123abc88 | 1294 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
1295 | btrfs_set_item_offset(leaf->items + i, ioff + dsize); |
1296 | } | |
be0e5c09 | 1297 | memmove(leaf->items + slot, leaf->items + slot + 1, |
0783fcfc | 1298 | sizeof(struct btrfs_item) * |
7518a238 | 1299 | (nritems - slot - 1)); |
be0e5c09 | 1300 | } |
7518a238 CM |
1301 | btrfs_set_header_nritems(&leaf->header, nritems - 1); |
1302 | nritems--; | |
74123bd7 | 1303 | /* delete the leaf if we've emptied it */ |
7518a238 | 1304 | if (nritems == 0) { |
eb60ceac | 1305 | if (leaf_buf == root->node) { |
7518a238 | 1306 | btrfs_set_header_level(&leaf->header, 0); |
02217ed2 | 1307 | BUG_ON(list_empty(&leaf_buf->dirty)); |
9a8dd150 | 1308 | } else { |
ed2ff2cb | 1309 | clean_tree_block(root, leaf_buf); |
bb803951 | 1310 | wret = del_ptr(root, path, 1, path->slots[1]); |
aa5d6bed CM |
1311 | if (wret) |
1312 | ret = wret; | |
234b63a0 | 1313 | wret = btrfs_free_extent(root, leaf_buf->blocknr, 1); |
0f70abe2 CM |
1314 | if (wret) |
1315 | ret = wret; | |
9a8dd150 | 1316 | } |
be0e5c09 | 1317 | } else { |
7518a238 | 1318 | int used = leaf_space_used(leaf, 0, nritems); |
aa5d6bed CM |
1319 | if (slot == 0) { |
1320 | wret = fixup_low_keys(root, path, | |
1321 | &leaf->items[0].key, 1); | |
1322 | if (wret) | |
1323 | ret = wret; | |
1324 | } | |
02217ed2 | 1325 | BUG_ON(list_empty(&leaf_buf->dirty)); |
aa5d6bed | 1326 | |
74123bd7 | 1327 | /* delete the leaf if it is mostly empty */ |
123abc88 | 1328 | if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) { |
be0e5c09 CM |
1329 | /* push_leaf_left fixes the path. |
1330 | * make sure the path still points to our leaf | |
1331 | * for possible call to del_ptr below | |
1332 | */ | |
4920c9ac | 1333 | slot = path->slots[1]; |
eb60ceac | 1334 | leaf_buf->count++; |
aa5d6bed CM |
1335 | wret = push_leaf_left(root, path, 1); |
1336 | if (wret < 0) | |
1337 | ret = wret; | |
f0930a37 | 1338 | if (path->nodes[0] == leaf_buf && |
7518a238 | 1339 | btrfs_header_nritems(&leaf->header)) { |
aa5d6bed CM |
1340 | wret = push_leaf_right(root, path, 1); |
1341 | if (wret < 0) | |
1342 | ret = wret; | |
1343 | } | |
7518a238 | 1344 | if (btrfs_header_nritems(&leaf->header) == 0) { |
5de08d7d | 1345 | u64 blocknr = leaf_buf->blocknr; |
ed2ff2cb | 1346 | clean_tree_block(root, leaf_buf); |
bb803951 | 1347 | wret = del_ptr(root, path, 1, slot); |
aa5d6bed CM |
1348 | if (wret) |
1349 | ret = wret; | |
234b63a0 CM |
1350 | btrfs_block_release(root, leaf_buf); |
1351 | wret = btrfs_free_extent(root, blocknr, 1); | |
0f70abe2 CM |
1352 | if (wret) |
1353 | ret = wret; | |
5de08d7d | 1354 | } else { |
234b63a0 | 1355 | btrfs_block_release(root, leaf_buf); |
be0e5c09 CM |
1356 | } |
1357 | } | |
1358 | } | |
aa5d6bed | 1359 | return ret; |
be0e5c09 CM |
1360 | } |
1361 | ||
97571fd0 CM |
1362 | /* |
1363 | * walk up the tree as far as required to find the next leaf. | |
0f70abe2 CM |
1364 | * returns 0 if it found something or 1 if there are no greater leaves. |
1365 | * returns < 0 on io errors. | |
97571fd0 | 1366 | */ |
234b63a0 | 1367 | int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) |
d97e63b6 CM |
1368 | { |
1369 | int slot; | |
1370 | int level = 1; | |
1371 | u64 blocknr; | |
234b63a0 CM |
1372 | struct btrfs_buffer *c; |
1373 | struct btrfs_buffer *next = NULL; | |
d97e63b6 | 1374 | |
234b63a0 | 1375 | while(level < BTRFS_MAX_LEVEL) { |
d97e63b6 | 1376 | if (!path->nodes[level]) |
0f70abe2 | 1377 | return 1; |
d97e63b6 CM |
1378 | slot = path->slots[level] + 1; |
1379 | c = path->nodes[level]; | |
7518a238 | 1380 | if (slot >= btrfs_header_nritems(&c->node.header)) { |
d97e63b6 CM |
1381 | level++; |
1382 | continue; | |
1383 | } | |
1d4f8a0c | 1384 | blocknr = btrfs_node_blockptr(&c->node, slot); |
cfaa7295 | 1385 | if (next) |
234b63a0 | 1386 | btrfs_block_release(root, next); |
d97e63b6 CM |
1387 | next = read_tree_block(root, blocknr); |
1388 | break; | |
1389 | } | |
1390 | path->slots[level] = slot; | |
1391 | while(1) { | |
1392 | level--; | |
1393 | c = path->nodes[level]; | |
234b63a0 | 1394 | btrfs_block_release(root, c); |
d97e63b6 CM |
1395 | path->nodes[level] = next; |
1396 | path->slots[level] = 0; | |
1397 | if (!level) | |
1398 | break; | |
1d4f8a0c CM |
1399 | next = read_tree_block(root, |
1400 | btrfs_node_blockptr(&next->node, 0)); | |
d97e63b6 CM |
1401 | } |
1402 | return 0; | |
1403 | } | |
1404 | ||
02217ed2 | 1405 |