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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 | |
e089f05c CM |
9 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
10 | *root, struct btrfs_path *path, int level); | |
11 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root | |
12 | *root, struct btrfs_path *path, int data_size); | |
13 | static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root | |
14 | *root, struct btrfs_buffer *dst, struct btrfs_buffer | |
15 | *src); | |
16 | static int balance_node_right(struct btrfs_trans_handle *trans, struct | |
17 | btrfs_root *root, struct btrfs_buffer *dst_buf, | |
234b63a0 | 18 | struct btrfs_buffer *src_buf); |
e089f05c CM |
19 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
20 | struct btrfs_path *path, int level, int slot); | |
d97e63b6 | 21 | |
234b63a0 | 22 | inline void btrfs_init_path(struct btrfs_path *p) |
be0e5c09 CM |
23 | { |
24 | memset(p, 0, sizeof(*p)); | |
25 | } | |
26 | ||
234b63a0 | 27 | void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p) |
eb60ceac CM |
28 | { |
29 | int i; | |
234b63a0 | 30 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
eb60ceac CM |
31 | if (!p->nodes[i]) |
32 | break; | |
234b63a0 | 33 | btrfs_block_release(root, p->nodes[i]); |
eb60ceac | 34 | } |
aa5d6bed | 35 | memset(p, 0, sizeof(*p)); |
eb60ceac CM |
36 | } |
37 | ||
e089f05c CM |
38 | static int btrfs_cow_block(struct btrfs_trans_handle *trans, struct btrfs_root |
39 | *root, struct btrfs_buffer *buf, struct btrfs_buffer | |
40 | *parent, int parent_slot, struct btrfs_buffer | |
41 | **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 | } | |
e089f05c | 49 | cow = btrfs_alloc_free_block(trans, 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; |
e089f05c | 53 | btrfs_inc_ref(trans, root, buf); |
02217ed2 CM |
54 | if (buf == root->node) { |
55 | root->node = cow; | |
56 | cow->count++; | |
a28ec197 | 57 | if (buf != root->commit_root) |
e089f05c | 58 | btrfs_free_extent(trans, root, buf->blocknr, 1, 1); |
234b63a0 | 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)); |
e089f05c | 64 | btrfs_free_extent(trans, root, buf->blocknr, 1, 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 | ||
e089f05c CM |
269 | static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root |
270 | *root, struct btrfs_path *path, int level) | |
bb803951 | 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); |
e089f05c CM |
313 | clean_tree_block(trans, root, mid_buf); |
314 | return btrfs_free_extent(trans, root, blocknr, 1, 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) { |
e089f05c CM |
327 | btrfs_cow_block(trans, root, left_buf, parent_buf, pslot - 1, |
328 | &left_buf); | |
bb803951 | 329 | left = &left_buf->node; |
7518a238 | 330 | orig_slot += btrfs_header_nritems(&left->header); |
e089f05c | 331 | wret = push_node_left(trans, root, left_buf, mid_buf); |
79f95c82 CM |
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) { |
e089f05c CM |
340 | btrfs_cow_block(trans, root, right_buf, parent_buf, pslot + 1, |
341 | &right_buf); | |
79f95c82 | 342 | right = &right_buf->node; |
e089f05c | 343 | wret = push_node_left(trans, root, mid_buf, right_buf); |
79f95c82 CM |
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); |
e089f05c | 349 | clean_tree_block(trans, root, right_buf); |
bb803951 CM |
350 | right_buf = NULL; |
351 | right = NULL; | |
e089f05c CM |
352 | wret = del_ptr(trans, root, path, level + 1, pslot + |
353 | 1); | |
bb803951 CM |
354 | if (wret) |
355 | ret = wret; | |
e089f05c | 356 | wret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 CM |
357 | if (wret) |
358 | ret = wret; | |
359 | } else { | |
123abc88 CM |
360 | memcpy(&parent->ptrs[pslot + 1].key, |
361 | &right->ptrs[0].key, | |
e2fa7227 | 362 | sizeof(struct btrfs_disk_key)); |
02217ed2 | 363 | BUG_ON(list_empty(&parent_buf->dirty)); |
bb803951 CM |
364 | } |
365 | } | |
7518a238 | 366 | if (btrfs_header_nritems(&mid->header) == 1) { |
79f95c82 CM |
367 | /* |
368 | * we're not allowed to leave a node with one item in the | |
369 | * tree during a delete. A deletion from lower in the tree | |
370 | * could try to delete the only pointer in this node. | |
371 | * So, pull some keys from the left. | |
372 | * There has to be a left pointer at this point because | |
373 | * otherwise we would have pulled some pointers from the | |
374 | * right | |
375 | */ | |
376 | BUG_ON(!left_buf); | |
e089f05c | 377 | wret = balance_node_right(trans, root, mid_buf, left_buf); |
79f95c82 CM |
378 | if (wret < 0) |
379 | ret = wret; | |
380 | BUG_ON(wret == 1); | |
381 | } | |
7518a238 | 382 | if (btrfs_header_nritems(&mid->header) == 0) { |
79f95c82 | 383 | /* we've managed to empty the middle node, drop it */ |
bb803951 | 384 | u64 blocknr = mid_buf->blocknr; |
234b63a0 | 385 | btrfs_block_release(root, mid_buf); |
e089f05c | 386 | clean_tree_block(trans, root, mid_buf); |
bb803951 CM |
387 | mid_buf = NULL; |
388 | mid = NULL; | |
e089f05c | 389 | wret = del_ptr(trans, root, path, level + 1, pslot); |
bb803951 CM |
390 | if (wret) |
391 | ret = wret; | |
e089f05c | 392 | wret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 CM |
393 | if (wret) |
394 | ret = wret; | |
79f95c82 CM |
395 | } else { |
396 | /* update the parent key to reflect our changes */ | |
123abc88 | 397 | memcpy(&parent->ptrs[pslot].key, &mid->ptrs[0].key, |
e2fa7227 | 398 | sizeof(struct btrfs_disk_key)); |
02217ed2 | 399 | BUG_ON(list_empty(&parent_buf->dirty)); |
79f95c82 | 400 | } |
bb803951 | 401 | |
79f95c82 | 402 | /* update the path */ |
bb803951 | 403 | if (left_buf) { |
7518a238 | 404 | if (btrfs_header_nritems(&left->header) > orig_slot) { |
bb803951 CM |
405 | left_buf->count++; // released below |
406 | path->nodes[level] = left_buf; | |
407 | path->slots[level + 1] -= 1; | |
408 | path->slots[level] = orig_slot; | |
409 | if (mid_buf) | |
234b63a0 | 410 | btrfs_block_release(root, mid_buf); |
bb803951 | 411 | } else { |
7518a238 | 412 | orig_slot -= btrfs_header_nritems(&left->header); |
bb803951 CM |
413 | path->slots[level] = orig_slot; |
414 | } | |
415 | } | |
79f95c82 | 416 | /* double check we haven't messed things up */ |
123abc88 | 417 | check_block(root, path, level); |
1d4f8a0c CM |
418 | if (orig_ptr != btrfs_node_blockptr(&path->nodes[level]->node, |
419 | path->slots[level])) | |
79f95c82 | 420 | BUG(); |
bb803951 CM |
421 | |
422 | if (right_buf) | |
234b63a0 | 423 | btrfs_block_release(root, right_buf); |
bb803951 | 424 | if (left_buf) |
234b63a0 | 425 | btrfs_block_release(root, left_buf); |
bb803951 CM |
426 | return ret; |
427 | } | |
428 | ||
74123bd7 CM |
429 | /* |
430 | * look for key in the tree. path is filled in with nodes along the way | |
431 | * if key is found, we return zero and you can find the item in the leaf | |
432 | * level of the path (level 0) | |
433 | * | |
434 | * If the key isn't found, the path points to the slot where it should | |
aa5d6bed CM |
435 | * be inserted, and 1 is returned. If there are other errors during the |
436 | * search a negative error number is returned. | |
97571fd0 CM |
437 | * |
438 | * if ins_len > 0, nodes and leaves will be split as we walk down the | |
439 | * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if | |
440 | * possible) | |
74123bd7 | 441 | */ |
e089f05c CM |
442 | int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root |
443 | *root, struct btrfs_key *key, struct btrfs_path *p, int | |
444 | ins_len, int cow) | |
be0e5c09 | 445 | { |
234b63a0 CM |
446 | struct btrfs_buffer *b; |
447 | struct btrfs_buffer *cow_buf; | |
448 | struct btrfs_node *c; | |
be0e5c09 CM |
449 | int slot; |
450 | int ret; | |
451 | int level; | |
5c680ed6 | 452 | |
bb803951 CM |
453 | again: |
454 | b = root->node; | |
eb60ceac CM |
455 | b->count++; |
456 | while (b) { | |
7518a238 | 457 | level = btrfs_header_level(&b->node.header); |
02217ed2 CM |
458 | if (cow) { |
459 | int wret; | |
e089f05c CM |
460 | wret = btrfs_cow_block(trans, root, b, p->nodes[level + |
461 | 1], p->slots[level + 1], | |
462 | &cow_buf); | |
02217ed2 CM |
463 | b = cow_buf; |
464 | } | |
465 | BUG_ON(!cow && ins_len); | |
eb60ceac | 466 | c = &b->node; |
eb60ceac | 467 | p->nodes[level] = b; |
123abc88 | 468 | ret = check_block(root, p, level); |
aa5d6bed CM |
469 | if (ret) |
470 | return -1; | |
be0e5c09 | 471 | ret = bin_search(c, key, &slot); |
7518a238 | 472 | if (!btrfs_is_leaf(c)) { |
be0e5c09 CM |
473 | if (ret && slot > 0) |
474 | slot -= 1; | |
475 | p->slots[level] = slot; | |
7518a238 | 476 | if (ins_len > 0 && btrfs_header_nritems(&c->header) == |
123abc88 | 477 | BTRFS_NODEPTRS_PER_BLOCK(root)) { |
e089f05c | 478 | int sret = split_node(trans, root, p, level); |
5c680ed6 CM |
479 | BUG_ON(sret > 0); |
480 | if (sret) | |
481 | return sret; | |
482 | b = p->nodes[level]; | |
483 | c = &b->node; | |
484 | slot = p->slots[level]; | |
bb803951 | 485 | } else if (ins_len < 0) { |
e089f05c CM |
486 | int sret = balance_level(trans, root, p, |
487 | level); | |
bb803951 CM |
488 | if (sret) |
489 | return sret; | |
490 | b = p->nodes[level]; | |
491 | if (!b) | |
492 | goto again; | |
493 | c = &b->node; | |
494 | slot = p->slots[level]; | |
7518a238 | 495 | BUG_ON(btrfs_header_nritems(&c->header) == 1); |
5c680ed6 | 496 | } |
1d4f8a0c | 497 | b = read_tree_block(root, btrfs_node_blockptr(c, slot)); |
be0e5c09 | 498 | } else { |
234b63a0 | 499 | struct btrfs_leaf *l = (struct btrfs_leaf *)c; |
be0e5c09 | 500 | p->slots[level] = slot; |
123abc88 | 501 | if (ins_len > 0 && btrfs_leaf_free_space(root, l) < |
0783fcfc | 502 | sizeof(struct btrfs_item) + ins_len) { |
e089f05c | 503 | int sret = split_leaf(trans, root, p, ins_len); |
5c680ed6 CM |
504 | BUG_ON(sret > 0); |
505 | if (sret) | |
506 | return sret; | |
507 | } | |
bb803951 | 508 | BUG_ON(root->node->count == 1); |
be0e5c09 CM |
509 | return ret; |
510 | } | |
511 | } | |
bb803951 | 512 | BUG_ON(root->node->count == 1); |
aa5d6bed | 513 | return 1; |
be0e5c09 CM |
514 | } |
515 | ||
74123bd7 CM |
516 | /* |
517 | * adjust the pointers going up the tree, starting at level | |
518 | * making sure the right key of each node is points to 'key'. | |
519 | * This is used after shifting pointers to the left, so it stops | |
520 | * fixing up pointers when a given leaf/node is not in slot 0 of the | |
521 | * higher levels | |
aa5d6bed CM |
522 | * |
523 | * If this fails to write a tree block, it returns -1, but continues | |
524 | * fixing up the blocks in ram so the tree is consistent. | |
74123bd7 | 525 | */ |
e089f05c CM |
526 | static int fixup_low_keys(struct btrfs_trans_handle *trans, struct btrfs_root |
527 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
528 | *key, int level) | |
be0e5c09 CM |
529 | { |
530 | int i; | |
aa5d6bed | 531 | int ret = 0; |
234b63a0 CM |
532 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
533 | struct btrfs_node *t; | |
be0e5c09 | 534 | int tslot = path->slots[i]; |
eb60ceac | 535 | if (!path->nodes[i]) |
be0e5c09 | 536 | break; |
eb60ceac | 537 | t = &path->nodes[i]->node; |
123abc88 | 538 | memcpy(&t->ptrs[tslot].key, key, sizeof(*key)); |
02217ed2 | 539 | BUG_ON(list_empty(&path->nodes[i]->dirty)); |
be0e5c09 CM |
540 | if (tslot != 0) |
541 | break; | |
542 | } | |
aa5d6bed | 543 | return ret; |
be0e5c09 CM |
544 | } |
545 | ||
74123bd7 CM |
546 | /* |
547 | * try to push data from one node into the next node left in the | |
79f95c82 | 548 | * tree. |
aa5d6bed CM |
549 | * |
550 | * returns 0 if some ptrs were pushed left, < 0 if there was some horrible | |
551 | * error, and > 0 if there was no room in the left hand block. | |
74123bd7 | 552 | */ |
e089f05c CM |
553 | static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root |
554 | *root, struct btrfs_buffer *dst_buf, struct | |
555 | btrfs_buffer *src_buf) | |
be0e5c09 | 556 | { |
234b63a0 CM |
557 | struct btrfs_node *src = &src_buf->node; |
558 | struct btrfs_node *dst = &dst_buf->node; | |
be0e5c09 | 559 | int push_items = 0; |
bb803951 CM |
560 | int src_nritems; |
561 | int dst_nritems; | |
aa5d6bed | 562 | int ret = 0; |
be0e5c09 | 563 | |
7518a238 CM |
564 | src_nritems = btrfs_header_nritems(&src->header); |
565 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 566 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
eb60ceac | 567 | if (push_items <= 0) { |
be0e5c09 | 568 | return 1; |
eb60ceac | 569 | } |
be0e5c09 | 570 | |
bb803951 | 571 | if (src_nritems < push_items) |
79f95c82 CM |
572 | push_items = src_nritems; |
573 | ||
123abc88 CM |
574 | memcpy(dst->ptrs + dst_nritems, src->ptrs, |
575 | push_items * sizeof(struct btrfs_key_ptr)); | |
bb803951 | 576 | if (push_items < src_nritems) { |
123abc88 | 577 | memmove(src->ptrs, src->ptrs + push_items, |
e2fa7227 | 578 | (src_nritems - push_items) * |
123abc88 | 579 | sizeof(struct btrfs_key_ptr)); |
bb803951 | 580 | } |
7518a238 CM |
581 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
582 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
02217ed2 CM |
583 | BUG_ON(list_empty(&src_buf->dirty)); |
584 | BUG_ON(list_empty(&dst_buf->dirty)); | |
79f95c82 CM |
585 | return ret; |
586 | } | |
587 | ||
588 | /* | |
589 | * try to push data from one node into the next node right in the | |
590 | * tree. | |
591 | * | |
592 | * returns 0 if some ptrs were pushed, < 0 if there was some horrible | |
593 | * error, and > 0 if there was no room in the right hand block. | |
594 | * | |
595 | * this will only push up to 1/2 the contents of the left node over | |
596 | */ | |
e089f05c CM |
597 | static int balance_node_right(struct btrfs_trans_handle *trans, struct |
598 | btrfs_root *root, struct btrfs_buffer *dst_buf, | |
234b63a0 | 599 | struct btrfs_buffer *src_buf) |
79f95c82 | 600 | { |
234b63a0 CM |
601 | struct btrfs_node *src = &src_buf->node; |
602 | struct btrfs_node *dst = &dst_buf->node; | |
79f95c82 CM |
603 | int push_items = 0; |
604 | int max_push; | |
605 | int src_nritems; | |
606 | int dst_nritems; | |
607 | int ret = 0; | |
79f95c82 | 608 | |
7518a238 CM |
609 | src_nritems = btrfs_header_nritems(&src->header); |
610 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 611 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
79f95c82 CM |
612 | if (push_items <= 0) { |
613 | return 1; | |
614 | } | |
615 | ||
616 | max_push = src_nritems / 2 + 1; | |
617 | /* don't try to empty the node */ | |
618 | if (max_push > src_nritems) | |
619 | return 1; | |
620 | if (max_push < push_items) | |
621 | push_items = max_push; | |
622 | ||
123abc88 CM |
623 | memmove(dst->ptrs + push_items, dst->ptrs, |
624 | dst_nritems * sizeof(struct btrfs_key_ptr)); | |
625 | memcpy(dst->ptrs, src->ptrs + src_nritems - push_items, | |
626 | push_items * sizeof(struct btrfs_key_ptr)); | |
79f95c82 | 627 | |
7518a238 CM |
628 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
629 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
79f95c82 | 630 | |
02217ed2 CM |
631 | BUG_ON(list_empty(&src_buf->dirty)); |
632 | BUG_ON(list_empty(&dst_buf->dirty)); | |
aa5d6bed | 633 | return ret; |
be0e5c09 CM |
634 | } |
635 | ||
97571fd0 CM |
636 | /* |
637 | * helper function to insert a new root level in the tree. | |
638 | * A new node is allocated, and a single item is inserted to | |
639 | * point to the existing root | |
aa5d6bed CM |
640 | * |
641 | * returns zero on success or < 0 on failure. | |
97571fd0 | 642 | */ |
e089f05c CM |
643 | static int insert_new_root(struct btrfs_trans_handle *trans, struct btrfs_root |
644 | *root, struct btrfs_path *path, int level) | |
5c680ed6 | 645 | { |
234b63a0 CM |
646 | struct btrfs_buffer *t; |
647 | struct btrfs_node *lower; | |
648 | struct btrfs_node *c; | |
e2fa7227 | 649 | struct btrfs_disk_key *lower_key; |
5c680ed6 CM |
650 | |
651 | BUG_ON(path->nodes[level]); | |
652 | BUG_ON(path->nodes[level-1] != root->node); | |
653 | ||
e089f05c | 654 | t = btrfs_alloc_free_block(trans, root); |
5c680ed6 | 655 | c = &t->node; |
123abc88 | 656 | memset(c, 0, root->blocksize); |
7518a238 CM |
657 | btrfs_set_header_nritems(&c->header, 1); |
658 | btrfs_set_header_level(&c->header, level); | |
659 | btrfs_set_header_blocknr(&c->header, t->blocknr); | |
660 | btrfs_set_header_parentid(&c->header, | |
661 | btrfs_header_parentid(&root->node->node.header)); | |
5c680ed6 | 662 | lower = &path->nodes[level-1]->node; |
7518a238 | 663 | if (btrfs_is_leaf(lower)) |
234b63a0 | 664 | lower_key = &((struct btrfs_leaf *)lower)->items[0].key; |
5c680ed6 | 665 | else |
123abc88 CM |
666 | lower_key = &lower->ptrs[0].key; |
667 | memcpy(&c->ptrs[0].key, lower_key, sizeof(struct btrfs_disk_key)); | |
1d4f8a0c | 668 | btrfs_set_node_blockptr(c, 0, path->nodes[level - 1]->blocknr); |
5c680ed6 | 669 | /* the super has an extra ref to root->node */ |
234b63a0 | 670 | btrfs_block_release(root, root->node); |
5c680ed6 CM |
671 | root->node = t; |
672 | t->count++; | |
5c680ed6 CM |
673 | path->nodes[level] = t; |
674 | path->slots[level] = 0; | |
675 | return 0; | |
676 | } | |
677 | ||
74123bd7 CM |
678 | /* |
679 | * worker function to insert a single pointer in a node. | |
680 | * the node should have enough room for the pointer already | |
97571fd0 | 681 | * |
74123bd7 CM |
682 | * slot and level indicate where you want the key to go, and |
683 | * blocknr is the block the key points to. | |
aa5d6bed CM |
684 | * |
685 | * returns zero on success and < 0 on any error | |
74123bd7 | 686 | */ |
e089f05c CM |
687 | static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root |
688 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
689 | *key, u64 blocknr, int slot, int level) | |
74123bd7 | 690 | { |
234b63a0 | 691 | struct btrfs_node *lower; |
74123bd7 | 692 | int nritems; |
5c680ed6 CM |
693 | |
694 | BUG_ON(!path->nodes[level]); | |
74123bd7 | 695 | lower = &path->nodes[level]->node; |
7518a238 | 696 | nritems = btrfs_header_nritems(&lower->header); |
74123bd7 CM |
697 | if (slot > nritems) |
698 | BUG(); | |
123abc88 | 699 | if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root)) |
74123bd7 CM |
700 | BUG(); |
701 | if (slot != nritems) { | |
123abc88 CM |
702 | memmove(lower->ptrs + slot + 1, lower->ptrs + slot, |
703 | (nritems - slot) * sizeof(struct btrfs_key_ptr)); | |
74123bd7 | 704 | } |
123abc88 | 705 | memcpy(&lower->ptrs[slot].key, key, sizeof(struct btrfs_disk_key)); |
1d4f8a0c | 706 | btrfs_set_node_blockptr(lower, slot, blocknr); |
7518a238 | 707 | btrfs_set_header_nritems(&lower->header, nritems + 1); |
02217ed2 | 708 | BUG_ON(list_empty(&path->nodes[level]->dirty)); |
74123bd7 CM |
709 | return 0; |
710 | } | |
711 | ||
97571fd0 CM |
712 | /* |
713 | * split the node at the specified level in path in two. | |
714 | * The path is corrected to point to the appropriate node after the split | |
715 | * | |
716 | * Before splitting this tries to make some room in the node by pushing | |
717 | * left and right, if either one works, it returns right away. | |
aa5d6bed CM |
718 | * |
719 | * returns 0 on success and < 0 on failure | |
97571fd0 | 720 | */ |
e089f05c CM |
721 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
722 | *root, struct btrfs_path *path, int level) | |
be0e5c09 | 723 | { |
234b63a0 CM |
724 | struct btrfs_buffer *t; |
725 | struct btrfs_node *c; | |
726 | struct btrfs_buffer *split_buffer; | |
727 | struct btrfs_node *split; | |
be0e5c09 | 728 | int mid; |
5c680ed6 | 729 | int ret; |
aa5d6bed | 730 | int wret; |
7518a238 | 731 | u32 c_nritems; |
eb60ceac | 732 | |
5c680ed6 CM |
733 | t = path->nodes[level]; |
734 | c = &t->node; | |
735 | if (t == root->node) { | |
736 | /* trying to split the root, lets make a new one */ | |
e089f05c | 737 | ret = insert_new_root(trans, root, path, level + 1); |
5c680ed6 CM |
738 | if (ret) |
739 | return ret; | |
be0e5c09 | 740 | } |
7518a238 | 741 | c_nritems = btrfs_header_nritems(&c->header); |
e089f05c | 742 | split_buffer = btrfs_alloc_free_block(trans, root); |
5c680ed6 | 743 | split = &split_buffer->node; |
7518a238 CM |
744 | btrfs_set_header_flags(&split->header, btrfs_header_flags(&c->header)); |
745 | btrfs_set_header_blocknr(&split->header, split_buffer->blocknr); | |
746 | btrfs_set_header_parentid(&split->header, | |
747 | btrfs_header_parentid(&root->node->node.header)); | |
748 | mid = (c_nritems + 1) / 2; | |
123abc88 CM |
749 | memcpy(split->ptrs, c->ptrs + mid, |
750 | (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); | |
7518a238 CM |
751 | btrfs_set_header_nritems(&split->header, c_nritems - mid); |
752 | btrfs_set_header_nritems(&c->header, mid); | |
aa5d6bed CM |
753 | ret = 0; |
754 | ||
02217ed2 | 755 | BUG_ON(list_empty(&t->dirty)); |
e089f05c | 756 | wret = insert_ptr(trans, root, path, &split->ptrs[0].key, |
123abc88 CM |
757 | split_buffer->blocknr, path->slots[level + 1] + 1, |
758 | level + 1); | |
aa5d6bed CM |
759 | if (wret) |
760 | ret = wret; | |
761 | ||
5de08d7d | 762 | if (path->slots[level] >= mid) { |
5c680ed6 | 763 | path->slots[level] -= mid; |
234b63a0 | 764 | btrfs_block_release(root, t); |
5c680ed6 CM |
765 | path->nodes[level] = split_buffer; |
766 | path->slots[level + 1] += 1; | |
767 | } else { | |
234b63a0 | 768 | btrfs_block_release(root, split_buffer); |
be0e5c09 | 769 | } |
aa5d6bed | 770 | return ret; |
be0e5c09 CM |
771 | } |
772 | ||
74123bd7 CM |
773 | /* |
774 | * how many bytes are required to store the items in a leaf. start | |
775 | * and nr indicate which items in the leaf to check. This totals up the | |
776 | * space used both by the item structs and the item data | |
777 | */ | |
234b63a0 | 778 | static int leaf_space_used(struct btrfs_leaf *l, int start, int nr) |
be0e5c09 CM |
779 | { |
780 | int data_len; | |
781 | int end = start + nr - 1; | |
782 | ||
783 | if (!nr) | |
784 | return 0; | |
0783fcfc CM |
785 | data_len = btrfs_item_end(l->items + start); |
786 | data_len = data_len - btrfs_item_offset(l->items + end); | |
787 | data_len += sizeof(struct btrfs_item) * nr; | |
be0e5c09 CM |
788 | return data_len; |
789 | } | |
790 | ||
00ec4c51 CM |
791 | /* |
792 | * push some data in the path leaf to the right, trying to free up at | |
793 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
aa5d6bed CM |
794 | * |
795 | * returns 1 if the push failed because the other node didn't have enough | |
796 | * room, 0 if everything worked out and < 0 if there were major errors. | |
00ec4c51 | 797 | */ |
e089f05c CM |
798 | static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root |
799 | *root, struct btrfs_path *path, int data_size) | |
00ec4c51 | 800 | { |
234b63a0 CM |
801 | struct btrfs_buffer *left_buf = path->nodes[0]; |
802 | struct btrfs_leaf *left = &left_buf->leaf; | |
803 | struct btrfs_leaf *right; | |
804 | struct btrfs_buffer *right_buf; | |
805 | struct btrfs_buffer *upper; | |
00ec4c51 CM |
806 | int slot; |
807 | int i; | |
808 | int free_space; | |
809 | int push_space = 0; | |
810 | int push_items = 0; | |
0783fcfc | 811 | struct btrfs_item *item; |
7518a238 CM |
812 | u32 left_nritems; |
813 | u32 right_nritems; | |
00ec4c51 CM |
814 | |
815 | slot = path->slots[1]; | |
816 | if (!path->nodes[1]) { | |
817 | return 1; | |
818 | } | |
819 | upper = path->nodes[1]; | |
7518a238 | 820 | if (slot >= btrfs_header_nritems(&upper->node.header) - 1) { |
00ec4c51 CM |
821 | return 1; |
822 | } | |
1d4f8a0c CM |
823 | right_buf = read_tree_block(root, btrfs_node_blockptr(&upper->node, |
824 | slot + 1)); | |
00ec4c51 | 825 | right = &right_buf->leaf; |
123abc88 | 826 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 827 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 828 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
829 | return 1; |
830 | } | |
02217ed2 | 831 | /* cow and double check */ |
e089f05c | 832 | btrfs_cow_block(trans, root, right_buf, upper, slot + 1, &right_buf); |
02217ed2 | 833 | right = &right_buf->leaf; |
123abc88 | 834 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 835 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 836 | btrfs_block_release(root, right_buf); |
02217ed2 CM |
837 | return 1; |
838 | } | |
839 | ||
7518a238 CM |
840 | left_nritems = btrfs_header_nritems(&left->header); |
841 | for (i = left_nritems - 1; i >= 0; i--) { | |
00ec4c51 CM |
842 | item = left->items + i; |
843 | if (path->slots[0] == i) | |
844 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
845 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
846 | free_space) | |
00ec4c51 CM |
847 | break; |
848 | push_items++; | |
0783fcfc | 849 | push_space += btrfs_item_size(item) + sizeof(*item); |
00ec4c51 CM |
850 | } |
851 | if (push_items == 0) { | |
234b63a0 | 852 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
853 | return 1; |
854 | } | |
7518a238 | 855 | right_nritems = btrfs_header_nritems(&right->header); |
00ec4c51 | 856 | /* push left to right */ |
0783fcfc | 857 | push_space = btrfs_item_end(left->items + left_nritems - push_items); |
123abc88 | 858 | push_space -= leaf_data_end(root, left); |
00ec4c51 | 859 | /* make room in the right data area */ |
123abc88 CM |
860 | memmove(btrfs_leaf_data(right) + leaf_data_end(root, right) - |
861 | push_space, btrfs_leaf_data(right) + leaf_data_end(root, right), | |
862 | BTRFS_LEAF_DATA_SIZE(root) - leaf_data_end(root, right)); | |
00ec4c51 | 863 | /* copy from the left data area */ |
123abc88 CM |
864 | memcpy(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - push_space, |
865 | btrfs_leaf_data(left) + leaf_data_end(root, left), push_space); | |
00ec4c51 | 866 | memmove(right->items + push_items, right->items, |
0783fcfc | 867 | right_nritems * sizeof(struct btrfs_item)); |
00ec4c51 | 868 | /* copy the items from left to right */ |
7518a238 | 869 | memcpy(right->items, left->items + left_nritems - push_items, |
0783fcfc | 870 | push_items * sizeof(struct btrfs_item)); |
00ec4c51 CM |
871 | |
872 | /* update the item pointers */ | |
7518a238 CM |
873 | right_nritems += push_items; |
874 | btrfs_set_header_nritems(&right->header, right_nritems); | |
123abc88 | 875 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
7518a238 | 876 | for (i = 0; i < right_nritems; i++) { |
0783fcfc CM |
877 | btrfs_set_item_offset(right->items + i, push_space - |
878 | btrfs_item_size(right->items + i)); | |
879 | push_space = btrfs_item_offset(right->items + i); | |
00ec4c51 | 880 | } |
7518a238 CM |
881 | left_nritems -= push_items; |
882 | btrfs_set_header_nritems(&left->header, left_nritems); | |
00ec4c51 | 883 | |
02217ed2 CM |
884 | BUG_ON(list_empty(&left_buf->dirty)); |
885 | BUG_ON(list_empty(&right_buf->dirty)); | |
123abc88 | 886 | memcpy(&upper->node.ptrs[slot + 1].key, |
e2fa7227 | 887 | &right->items[0].key, sizeof(struct btrfs_disk_key)); |
02217ed2 CM |
888 | BUG_ON(list_empty(&upper->dirty)); |
889 | ||
00ec4c51 | 890 | /* then fixup the leaf pointer in the path */ |
7518a238 CM |
891 | if (path->slots[0] >= left_nritems) { |
892 | path->slots[0] -= left_nritems; | |
234b63a0 | 893 | btrfs_block_release(root, path->nodes[0]); |
00ec4c51 CM |
894 | path->nodes[0] = right_buf; |
895 | path->slots[1] += 1; | |
896 | } else { | |
234b63a0 | 897 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
898 | } |
899 | return 0; | |
900 | } | |
74123bd7 CM |
901 | /* |
902 | * push some data in the path leaf to the left, trying to free up at | |
903 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
904 | */ | |
e089f05c CM |
905 | static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root |
906 | *root, struct btrfs_path *path, int data_size) | |
be0e5c09 | 907 | { |
234b63a0 CM |
908 | struct btrfs_buffer *right_buf = path->nodes[0]; |
909 | struct btrfs_leaf *right = &right_buf->leaf; | |
910 | struct btrfs_buffer *t; | |
911 | struct btrfs_leaf *left; | |
be0e5c09 CM |
912 | int slot; |
913 | int i; | |
914 | int free_space; | |
915 | int push_space = 0; | |
916 | int push_items = 0; | |
0783fcfc | 917 | struct btrfs_item *item; |
7518a238 | 918 | u32 old_left_nritems; |
aa5d6bed CM |
919 | int ret = 0; |
920 | int wret; | |
be0e5c09 CM |
921 | |
922 | slot = path->slots[1]; | |
923 | if (slot == 0) { | |
924 | return 1; | |
925 | } | |
926 | if (!path->nodes[1]) { | |
927 | return 1; | |
928 | } | |
1d4f8a0c CM |
929 | t = read_tree_block(root, btrfs_node_blockptr(&path->nodes[1]->node, |
930 | slot - 1)); | |
eb60ceac | 931 | left = &t->leaf; |
123abc88 | 932 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 933 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 934 | btrfs_block_release(root, t); |
be0e5c09 CM |
935 | return 1; |
936 | } | |
02217ed2 CM |
937 | |
938 | /* cow and double check */ | |
e089f05c | 939 | btrfs_cow_block(trans, root, t, path->nodes[1], slot - 1, &t); |
02217ed2 | 940 | left = &t->leaf; |
123abc88 | 941 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 942 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 943 | btrfs_block_release(root, t); |
02217ed2 CM |
944 | return 1; |
945 | } | |
946 | ||
7518a238 | 947 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
be0e5c09 CM |
948 | item = right->items + i; |
949 | if (path->slots[0] == i) | |
950 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
951 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
952 | free_space) | |
be0e5c09 CM |
953 | break; |
954 | push_items++; | |
0783fcfc | 955 | push_space += btrfs_item_size(item) + sizeof(*item); |
be0e5c09 CM |
956 | } |
957 | if (push_items == 0) { | |
234b63a0 | 958 | btrfs_block_release(root, t); |
be0e5c09 CM |
959 | return 1; |
960 | } | |
961 | /* push data from right to left */ | |
7518a238 | 962 | memcpy(left->items + btrfs_header_nritems(&left->header), |
0783fcfc | 963 | right->items, push_items * sizeof(struct btrfs_item)); |
123abc88 | 964 | push_space = BTRFS_LEAF_DATA_SIZE(root) - |
0783fcfc | 965 | btrfs_item_offset(right->items + push_items -1); |
123abc88 CM |
966 | memcpy(btrfs_leaf_data(left) + leaf_data_end(root, left) - push_space, |
967 | btrfs_leaf_data(right) + | |
968 | btrfs_item_offset(right->items + push_items - 1), | |
be0e5c09 | 969 | push_space); |
7518a238 | 970 | old_left_nritems = btrfs_header_nritems(&left->header); |
eb60ceac CM |
971 | BUG_ON(old_left_nritems < 0); |
972 | ||
0783fcfc | 973 | for (i = old_left_nritems; i < old_left_nritems + push_items; i++) { |
123abc88 CM |
974 | u32 ioff = btrfs_item_offset(left->items + i); |
975 | btrfs_set_item_offset(left->items + i, ioff - | |
976 | (BTRFS_LEAF_DATA_SIZE(root) - | |
0783fcfc CM |
977 | btrfs_item_offset(left->items + |
978 | old_left_nritems - 1))); | |
be0e5c09 | 979 | } |
7518a238 | 980 | btrfs_set_header_nritems(&left->header, old_left_nritems + push_items); |
be0e5c09 CM |
981 | |
982 | /* fixup right node */ | |
0783fcfc | 983 | push_space = btrfs_item_offset(right->items + push_items - 1) - |
123abc88 CM |
984 | leaf_data_end(root, right); |
985 | memmove(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - | |
986 | push_space, btrfs_leaf_data(right) + | |
987 | leaf_data_end(root, right), push_space); | |
be0e5c09 | 988 | memmove(right->items, right->items + push_items, |
7518a238 | 989 | (btrfs_header_nritems(&right->header) - push_items) * |
0783fcfc | 990 | sizeof(struct btrfs_item)); |
7518a238 CM |
991 | btrfs_set_header_nritems(&right->header, |
992 | btrfs_header_nritems(&right->header) - | |
993 | push_items); | |
123abc88 | 994 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
eb60ceac | 995 | |
7518a238 | 996 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
0783fcfc CM |
997 | btrfs_set_item_offset(right->items + i, push_space - |
998 | btrfs_item_size(right->items + i)); | |
999 | push_space = btrfs_item_offset(right->items + i); | |
be0e5c09 | 1000 | } |
eb60ceac | 1001 | |
02217ed2 CM |
1002 | BUG_ON(list_empty(&t->dirty)); |
1003 | BUG_ON(list_empty(&right_buf->dirty)); | |
eb60ceac | 1004 | |
e089f05c | 1005 | wret = fixup_low_keys(trans, root, path, &right->items[0].key, 1); |
aa5d6bed CM |
1006 | if (wret) |
1007 | ret = wret; | |
be0e5c09 CM |
1008 | |
1009 | /* then fixup the leaf pointer in the path */ | |
1010 | if (path->slots[0] < push_items) { | |
1011 | path->slots[0] += old_left_nritems; | |
234b63a0 | 1012 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1013 | path->nodes[0] = t; |
be0e5c09 CM |
1014 | path->slots[1] -= 1; |
1015 | } else { | |
234b63a0 | 1016 | btrfs_block_release(root, t); |
be0e5c09 CM |
1017 | path->slots[0] -= push_items; |
1018 | } | |
eb60ceac | 1019 | BUG_ON(path->slots[0] < 0); |
aa5d6bed | 1020 | return ret; |
be0e5c09 CM |
1021 | } |
1022 | ||
74123bd7 CM |
1023 | /* |
1024 | * split the path's leaf in two, making sure there is at least data_size | |
1025 | * available for the resulting leaf level of the path. | |
aa5d6bed CM |
1026 | * |
1027 | * returns 0 if all went well and < 0 on failure. | |
74123bd7 | 1028 | */ |
e089f05c CM |
1029 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root |
1030 | *root, struct btrfs_path *path, int data_size) | |
be0e5c09 | 1031 | { |
234b63a0 CM |
1032 | struct btrfs_buffer *l_buf; |
1033 | struct btrfs_leaf *l; | |
7518a238 | 1034 | u32 nritems; |
eb60ceac CM |
1035 | int mid; |
1036 | int slot; | |
234b63a0 CM |
1037 | struct btrfs_leaf *right; |
1038 | struct btrfs_buffer *right_buffer; | |
0783fcfc | 1039 | int space_needed = data_size + sizeof(struct btrfs_item); |
be0e5c09 CM |
1040 | int data_copy_size; |
1041 | int rt_data_off; | |
1042 | int i; | |
1043 | int ret; | |
aa5d6bed CM |
1044 | int wret; |
1045 | ||
e089f05c | 1046 | wret = push_leaf_left(trans, root, path, data_size); |
eaee50e8 CM |
1047 | if (wret < 0) |
1048 | return wret; | |
1049 | if (wret) { | |
e089f05c | 1050 | wret = push_leaf_right(trans, root, path, data_size); |
eaee50e8 CM |
1051 | if (wret < 0) |
1052 | return wret; | |
1053 | } | |
aa5d6bed CM |
1054 | l_buf = path->nodes[0]; |
1055 | l = &l_buf->leaf; | |
1056 | ||
1057 | /* did the pushes work? */ | |
123abc88 CM |
1058 | if (btrfs_leaf_free_space(root, l) >= |
1059 | sizeof(struct btrfs_item) + data_size) | |
aa5d6bed CM |
1060 | return 0; |
1061 | ||
5c680ed6 | 1062 | if (!path->nodes[1]) { |
e089f05c | 1063 | ret = insert_new_root(trans, root, path, 1); |
5c680ed6 CM |
1064 | if (ret) |
1065 | return ret; | |
1066 | } | |
eb60ceac | 1067 | slot = path->slots[0]; |
7518a238 | 1068 | nritems = btrfs_header_nritems(&l->header); |
eb60ceac | 1069 | mid = (nritems + 1)/ 2; |
e089f05c | 1070 | right_buffer = btrfs_alloc_free_block(trans, root); |
eb60ceac CM |
1071 | BUG_ON(!right_buffer); |
1072 | BUG_ON(mid == nritems); | |
1073 | right = &right_buffer->leaf; | |
123abc88 | 1074 | memset(&right->header, 0, sizeof(right->header)); |
be0e5c09 | 1075 | if (mid <= slot) { |
97571fd0 | 1076 | /* FIXME, just alloc a new leaf here */ |
be0e5c09 | 1077 | if (leaf_space_used(l, mid, nritems - mid) + space_needed > |
123abc88 | 1078 | BTRFS_LEAF_DATA_SIZE(root)) |
be0e5c09 CM |
1079 | BUG(); |
1080 | } else { | |
97571fd0 | 1081 | /* FIXME, just alloc a new leaf here */ |
be0e5c09 | 1082 | if (leaf_space_used(l, 0, mid + 1) + space_needed > |
123abc88 | 1083 | BTRFS_LEAF_DATA_SIZE(root)) |
be0e5c09 CM |
1084 | BUG(); |
1085 | } | |
7518a238 CM |
1086 | btrfs_set_header_nritems(&right->header, nritems - mid); |
1087 | btrfs_set_header_blocknr(&right->header, right_buffer->blocknr); | |
1088 | btrfs_set_header_level(&right->header, 0); | |
1089 | btrfs_set_header_parentid(&right->header, | |
1090 | btrfs_header_parentid(&root->node->node.header)); | |
123abc88 CM |
1091 | data_copy_size = btrfs_item_end(l->items + mid) - |
1092 | leaf_data_end(root, l); | |
be0e5c09 | 1093 | memcpy(right->items, l->items + mid, |
0783fcfc | 1094 | (nritems - mid) * sizeof(struct btrfs_item)); |
123abc88 CM |
1095 | memcpy(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - |
1096 | data_copy_size, btrfs_leaf_data(l) + | |
1097 | leaf_data_end(root, l), data_copy_size); | |
1098 | rt_data_off = BTRFS_LEAF_DATA_SIZE(root) - | |
1099 | btrfs_item_end(l->items + mid); | |
74123bd7 | 1100 | |
0783fcfc | 1101 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
123abc88 | 1102 | u32 ioff = btrfs_item_offset(right->items + i); |
0783fcfc CM |
1103 | btrfs_set_item_offset(right->items + i, ioff + rt_data_off); |
1104 | } | |
74123bd7 | 1105 | |
7518a238 | 1106 | btrfs_set_header_nritems(&l->header, mid); |
aa5d6bed | 1107 | ret = 0; |
e089f05c | 1108 | wret = insert_ptr(trans, root, path, &right->items[0].key, |
5c680ed6 | 1109 | right_buffer->blocknr, path->slots[1] + 1, 1); |
aa5d6bed CM |
1110 | if (wret) |
1111 | ret = wret; | |
02217ed2 CM |
1112 | BUG_ON(list_empty(&right_buffer->dirty)); |
1113 | BUG_ON(list_empty(&l_buf->dirty)); | |
eb60ceac | 1114 | BUG_ON(path->slots[0] != slot); |
be0e5c09 | 1115 | if (mid <= slot) { |
234b63a0 | 1116 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1117 | path->nodes[0] = right_buffer; |
be0e5c09 CM |
1118 | path->slots[0] -= mid; |
1119 | path->slots[1] += 1; | |
eb60ceac | 1120 | } else |
234b63a0 | 1121 | btrfs_block_release(root, right_buffer); |
eb60ceac | 1122 | BUG_ON(path->slots[0] < 0); |
be0e5c09 CM |
1123 | return ret; |
1124 | } | |
1125 | ||
74123bd7 CM |
1126 | /* |
1127 | * Given a key and some data, insert an item into the tree. | |
1128 | * This does all the path init required, making room in the tree if needed. | |
1129 | */ | |
e089f05c CM |
1130 | int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1131 | *root, struct btrfs_path *path, struct btrfs_key | |
1132 | *cpu_key, u32 data_size) | |
be0e5c09 | 1133 | { |
aa5d6bed | 1134 | int ret = 0; |
be0e5c09 | 1135 | int slot; |
eb60ceac | 1136 | int slot_orig; |
234b63a0 CM |
1137 | struct btrfs_leaf *leaf; |
1138 | struct btrfs_buffer *leaf_buf; | |
7518a238 | 1139 | u32 nritems; |
be0e5c09 | 1140 | unsigned int data_end; |
e2fa7227 CM |
1141 | struct btrfs_disk_key disk_key; |
1142 | ||
1143 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); | |
be0e5c09 | 1144 | |
74123bd7 | 1145 | /* create a root if there isn't one */ |
5c680ed6 | 1146 | if (!root->node) |
cfaa7295 | 1147 | BUG(); |
e089f05c | 1148 | ret = btrfs_search_slot(trans, root, cpu_key, path, data_size, 1); |
eb60ceac | 1149 | if (ret == 0) { |
62e2749e | 1150 | btrfs_release_path(root, path); |
f0930a37 | 1151 | return -EEXIST; |
aa5d6bed | 1152 | } |
ed2ff2cb CM |
1153 | if (ret < 0) |
1154 | goto out; | |
be0e5c09 | 1155 | |
62e2749e CM |
1156 | slot_orig = path->slots[0]; |
1157 | leaf_buf = path->nodes[0]; | |
eb60ceac | 1158 | leaf = &leaf_buf->leaf; |
74123bd7 | 1159 | |
7518a238 | 1160 | nritems = btrfs_header_nritems(&leaf->header); |
123abc88 | 1161 | data_end = leaf_data_end(root, leaf); |
eb60ceac | 1162 | |
123abc88 | 1163 | if (btrfs_leaf_free_space(root, leaf) < |
234b63a0 | 1164 | sizeof(struct btrfs_item) + data_size) |
be0e5c09 CM |
1165 | BUG(); |
1166 | ||
62e2749e | 1167 | slot = path->slots[0]; |
eb60ceac | 1168 | BUG_ON(slot < 0); |
be0e5c09 CM |
1169 | if (slot != nritems) { |
1170 | int i; | |
0783fcfc | 1171 | unsigned int old_data = btrfs_item_end(leaf->items + slot); |
be0e5c09 CM |
1172 | |
1173 | /* | |
1174 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1175 | */ | |
1176 | /* first correct the data pointers */ | |
0783fcfc | 1177 | for (i = slot; i < nritems; i++) { |
123abc88 | 1178 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
1179 | btrfs_set_item_offset(leaf->items + i, |
1180 | ioff - data_size); | |
1181 | } | |
be0e5c09 CM |
1182 | |
1183 | /* shift the items */ | |
1184 | memmove(leaf->items + slot + 1, leaf->items + slot, | |
0783fcfc | 1185 | (nritems - slot) * sizeof(struct btrfs_item)); |
be0e5c09 CM |
1186 | |
1187 | /* shift the data */ | |
123abc88 CM |
1188 | memmove(btrfs_leaf_data(leaf) + data_end - data_size, |
1189 | btrfs_leaf_data(leaf) + | |
be0e5c09 CM |
1190 | data_end, old_data - data_end); |
1191 | data_end = old_data; | |
1192 | } | |
62e2749e | 1193 | /* setup the item for the new data */ |
e2fa7227 CM |
1194 | memcpy(&leaf->items[slot].key, &disk_key, |
1195 | sizeof(struct btrfs_disk_key)); | |
0783fcfc CM |
1196 | btrfs_set_item_offset(leaf->items + slot, data_end - data_size); |
1197 | btrfs_set_item_size(leaf->items + slot, data_size); | |
7518a238 | 1198 | btrfs_set_header_nritems(&leaf->header, nritems + 1); |
aa5d6bed CM |
1199 | |
1200 | ret = 0; | |
8e19f2cd | 1201 | if (slot == 0) |
e089f05c | 1202 | ret = fixup_low_keys(trans, root, path, &disk_key, 1); |
aa5d6bed | 1203 | |
02217ed2 | 1204 | BUG_ON(list_empty(&leaf_buf->dirty)); |
123abc88 | 1205 | if (btrfs_leaf_free_space(root, leaf) < 0) |
be0e5c09 | 1206 | BUG(); |
62e2749e | 1207 | check_leaf(root, path, 0); |
ed2ff2cb | 1208 | out: |
62e2749e CM |
1209 | return ret; |
1210 | } | |
1211 | ||
1212 | /* | |
1213 | * Given a key and some data, insert an item into the tree. | |
1214 | * This does all the path init required, making room in the tree if needed. | |
1215 | */ | |
e089f05c CM |
1216 | int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1217 | *root, struct btrfs_key *cpu_key, void *data, u32 | |
1218 | data_size) | |
62e2749e CM |
1219 | { |
1220 | int ret = 0; | |
1221 | struct btrfs_path path; | |
1222 | u8 *ptr; | |
1223 | ||
1224 | btrfs_init_path(&path); | |
e089f05c | 1225 | ret = btrfs_insert_empty_item(trans, root, &path, cpu_key, data_size); |
62e2749e CM |
1226 | if (!ret) { |
1227 | ptr = btrfs_item_ptr(&path.nodes[0]->leaf, path.slots[0], u8); | |
1228 | memcpy(ptr, data, data_size); | |
1229 | } | |
234b63a0 | 1230 | btrfs_release_path(root, &path); |
aa5d6bed | 1231 | return ret; |
be0e5c09 CM |
1232 | } |
1233 | ||
74123bd7 | 1234 | /* |
5de08d7d | 1235 | * delete the pointer from a given node. |
74123bd7 CM |
1236 | * |
1237 | * If the delete empties a node, the node is removed from the tree, | |
1238 | * continuing all the way the root if required. The root is converted into | |
1239 | * a leaf if all the nodes are emptied. | |
1240 | */ | |
e089f05c CM |
1241 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
1242 | struct btrfs_path *path, int level, int slot) | |
be0e5c09 | 1243 | { |
234b63a0 CM |
1244 | struct btrfs_node *node; |
1245 | struct btrfs_buffer *parent = path->nodes[level]; | |
7518a238 | 1246 | u32 nritems; |
aa5d6bed | 1247 | int ret = 0; |
bb803951 | 1248 | int wret; |
be0e5c09 | 1249 | |
bb803951 | 1250 | node = &parent->node; |
7518a238 | 1251 | nritems = btrfs_header_nritems(&node->header); |
bb803951 | 1252 | if (slot != nritems -1) { |
123abc88 CM |
1253 | memmove(node->ptrs + slot, node->ptrs + slot + 1, |
1254 | sizeof(struct btrfs_key_ptr) * (nritems - slot - 1)); | |
bb803951 | 1255 | } |
7518a238 CM |
1256 | nritems--; |
1257 | btrfs_set_header_nritems(&node->header, nritems); | |
1258 | if (nritems == 0 && parent == root->node) { | |
1259 | BUG_ON(btrfs_header_level(&root->node->node.header) != 1); | |
bb803951 | 1260 | /* just turn the root into a leaf and break */ |
7518a238 | 1261 | btrfs_set_header_level(&root->node->node.header, 0); |
bb803951 | 1262 | } else if (slot == 0) { |
e089f05c | 1263 | wret = fixup_low_keys(trans, root, path, &node->ptrs[0].key, |
123abc88 | 1264 | level + 1); |
0f70abe2 CM |
1265 | if (wret) |
1266 | ret = wret; | |
be0e5c09 | 1267 | } |
02217ed2 | 1268 | BUG_ON(list_empty(&parent->dirty)); |
aa5d6bed | 1269 | return ret; |
be0e5c09 CM |
1270 | } |
1271 | ||
74123bd7 CM |
1272 | /* |
1273 | * delete the item at the leaf level in path. If that empties | |
1274 | * the leaf, remove it from the tree | |
1275 | */ | |
e089f05c CM |
1276 | int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
1277 | struct btrfs_path *path) | |
be0e5c09 | 1278 | { |
be0e5c09 | 1279 | int slot; |
234b63a0 CM |
1280 | struct btrfs_leaf *leaf; |
1281 | struct btrfs_buffer *leaf_buf; | |
be0e5c09 CM |
1282 | int doff; |
1283 | int dsize; | |
aa5d6bed CM |
1284 | int ret = 0; |
1285 | int wret; | |
7518a238 | 1286 | u32 nritems; |
be0e5c09 | 1287 | |
eb60ceac CM |
1288 | leaf_buf = path->nodes[0]; |
1289 | leaf = &leaf_buf->leaf; | |
4920c9ac | 1290 | slot = path->slots[0]; |
0783fcfc CM |
1291 | doff = btrfs_item_offset(leaf->items + slot); |
1292 | dsize = btrfs_item_size(leaf->items + slot); | |
7518a238 | 1293 | nritems = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 1294 | |
7518a238 | 1295 | if (slot != nritems - 1) { |
be0e5c09 | 1296 | int i; |
123abc88 CM |
1297 | int data_end = leaf_data_end(root, leaf); |
1298 | memmove(btrfs_leaf_data(leaf) + data_end + dsize, | |
1299 | btrfs_leaf_data(leaf) + data_end, | |
be0e5c09 | 1300 | doff - data_end); |
0783fcfc | 1301 | for (i = slot + 1; i < nritems; i++) { |
123abc88 | 1302 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
1303 | btrfs_set_item_offset(leaf->items + i, ioff + dsize); |
1304 | } | |
be0e5c09 | 1305 | memmove(leaf->items + slot, leaf->items + slot + 1, |
0783fcfc | 1306 | sizeof(struct btrfs_item) * |
7518a238 | 1307 | (nritems - slot - 1)); |
be0e5c09 | 1308 | } |
7518a238 CM |
1309 | btrfs_set_header_nritems(&leaf->header, nritems - 1); |
1310 | nritems--; | |
74123bd7 | 1311 | /* delete the leaf if we've emptied it */ |
7518a238 | 1312 | if (nritems == 0) { |
eb60ceac | 1313 | if (leaf_buf == root->node) { |
7518a238 | 1314 | btrfs_set_header_level(&leaf->header, 0); |
02217ed2 | 1315 | BUG_ON(list_empty(&leaf_buf->dirty)); |
9a8dd150 | 1316 | } else { |
e089f05c CM |
1317 | clean_tree_block(trans, root, leaf_buf); |
1318 | wret = del_ptr(trans, root, path, 1, path->slots[1]); | |
aa5d6bed CM |
1319 | if (wret) |
1320 | ret = wret; | |
e089f05c CM |
1321 | wret = btrfs_free_extent(trans, root, |
1322 | leaf_buf->blocknr, 1, 1); | |
0f70abe2 CM |
1323 | if (wret) |
1324 | ret = wret; | |
9a8dd150 | 1325 | } |
be0e5c09 | 1326 | } else { |
7518a238 | 1327 | int used = leaf_space_used(leaf, 0, nritems); |
aa5d6bed | 1328 | if (slot == 0) { |
e089f05c CM |
1329 | wret = fixup_low_keys(trans, root, path, |
1330 | &leaf->items[0].key, 1); | |
aa5d6bed CM |
1331 | if (wret) |
1332 | ret = wret; | |
1333 | } | |
02217ed2 | 1334 | BUG_ON(list_empty(&leaf_buf->dirty)); |
aa5d6bed | 1335 | |
74123bd7 | 1336 | /* delete the leaf if it is mostly empty */ |
123abc88 | 1337 | if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) { |
be0e5c09 CM |
1338 | /* push_leaf_left fixes the path. |
1339 | * make sure the path still points to our leaf | |
1340 | * for possible call to del_ptr below | |
1341 | */ | |
4920c9ac | 1342 | slot = path->slots[1]; |
eb60ceac | 1343 | leaf_buf->count++; |
e089f05c | 1344 | wret = push_leaf_left(trans, root, path, 1); |
aa5d6bed CM |
1345 | if (wret < 0) |
1346 | ret = wret; | |
f0930a37 | 1347 | if (path->nodes[0] == leaf_buf && |
7518a238 | 1348 | btrfs_header_nritems(&leaf->header)) { |
e089f05c | 1349 | wret = push_leaf_right(trans, root, path, 1); |
aa5d6bed CM |
1350 | if (wret < 0) |
1351 | ret = wret; | |
1352 | } | |
7518a238 | 1353 | if (btrfs_header_nritems(&leaf->header) == 0) { |
5de08d7d | 1354 | u64 blocknr = leaf_buf->blocknr; |
e089f05c CM |
1355 | clean_tree_block(trans, root, leaf_buf); |
1356 | wret = del_ptr(trans, root, path, 1, slot); | |
aa5d6bed CM |
1357 | if (wret) |
1358 | ret = wret; | |
234b63a0 | 1359 | btrfs_block_release(root, leaf_buf); |
e089f05c CM |
1360 | wret = btrfs_free_extent(trans, root, blocknr, |
1361 | 1, 1); | |
0f70abe2 CM |
1362 | if (wret) |
1363 | ret = wret; | |
5de08d7d | 1364 | } else { |
234b63a0 | 1365 | btrfs_block_release(root, leaf_buf); |
be0e5c09 CM |
1366 | } |
1367 | } | |
1368 | } | |
aa5d6bed | 1369 | return ret; |
be0e5c09 CM |
1370 | } |
1371 | ||
97571fd0 CM |
1372 | /* |
1373 | * walk up the tree as far as required to find the next leaf. | |
0f70abe2 CM |
1374 | * returns 0 if it found something or 1 if there are no greater leaves. |
1375 | * returns < 0 on io errors. | |
97571fd0 | 1376 | */ |
234b63a0 | 1377 | int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) |
d97e63b6 CM |
1378 | { |
1379 | int slot; | |
1380 | int level = 1; | |
1381 | u64 blocknr; | |
234b63a0 CM |
1382 | struct btrfs_buffer *c; |
1383 | struct btrfs_buffer *next = NULL; | |
d97e63b6 | 1384 | |
234b63a0 | 1385 | while(level < BTRFS_MAX_LEVEL) { |
d97e63b6 | 1386 | if (!path->nodes[level]) |
0f70abe2 | 1387 | return 1; |
d97e63b6 CM |
1388 | slot = path->slots[level] + 1; |
1389 | c = path->nodes[level]; | |
7518a238 | 1390 | if (slot >= btrfs_header_nritems(&c->node.header)) { |
d97e63b6 CM |
1391 | level++; |
1392 | continue; | |
1393 | } | |
1d4f8a0c | 1394 | blocknr = btrfs_node_blockptr(&c->node, slot); |
cfaa7295 | 1395 | if (next) |
234b63a0 | 1396 | btrfs_block_release(root, next); |
d97e63b6 CM |
1397 | next = read_tree_block(root, blocknr); |
1398 | break; | |
1399 | } | |
1400 | path->slots[level] = slot; | |
1401 | while(1) { | |
1402 | level--; | |
1403 | c = path->nodes[level]; | |
234b63a0 | 1404 | btrfs_block_release(root, c); |
d97e63b6 CM |
1405 | path->nodes[level] = next; |
1406 | path->slots[level] = 0; | |
1407 | if (!level) | |
1408 | break; | |
1d4f8a0c CM |
1409 | next = read_tree_block(root, |
1410 | btrfs_node_blockptr(&next->node, 0)); | |
d97e63b6 CM |
1411 | } |
1412 | return 0; | |
1413 | } |