Commit | Line | Data |
---|---|---|
2e635a27 | 1 | #include <linux/module.h> |
eb60ceac CM |
2 | #include "ctree.h" |
3 | #include "disk-io.h" | |
9a8dd150 | 4 | |
e089f05c CM |
5 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
6 | *root, struct btrfs_path *path, int level); | |
7 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root | |
8 | *root, struct btrfs_path *path, int data_size); | |
9 | static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root | |
e20d96d6 | 10 | *root, struct buffer_head *dst, struct buffer_head |
e089f05c CM |
11 | *src); |
12 | static int balance_node_right(struct btrfs_trans_handle *trans, struct | |
e20d96d6 CM |
13 | btrfs_root *root, struct buffer_head *dst_buf, |
14 | struct buffer_head *src_buf); | |
e089f05c CM |
15 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
16 | struct btrfs_path *path, int level, int slot); | |
d97e63b6 | 17 | |
234b63a0 | 18 | inline void btrfs_init_path(struct btrfs_path *p) |
be0e5c09 CM |
19 | { |
20 | memset(p, 0, sizeof(*p)); | |
21 | } | |
22 | ||
234b63a0 | 23 | void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p) |
eb60ceac CM |
24 | { |
25 | int i; | |
234b63a0 | 26 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
eb60ceac CM |
27 | if (!p->nodes[i]) |
28 | break; | |
234b63a0 | 29 | btrfs_block_release(root, p->nodes[i]); |
eb60ceac | 30 | } |
aa5d6bed | 31 | memset(p, 0, sizeof(*p)); |
eb60ceac CM |
32 | } |
33 | ||
e089f05c | 34 | static int btrfs_cow_block(struct btrfs_trans_handle *trans, struct btrfs_root |
e20d96d6 CM |
35 | *root, struct buffer_head *buf, struct buffer_head |
36 | *parent, int parent_slot, struct buffer_head | |
e089f05c | 37 | **cow_ret) |
02217ed2 | 38 | { |
e20d96d6 CM |
39 | struct buffer_head *cow; |
40 | struct btrfs_node *cow_node; | |
02217ed2 | 41 | |
d5719762 | 42 | if (buffer_dirty(buf)) { |
02217ed2 CM |
43 | *cow_ret = buf; |
44 | return 0; | |
45 | } | |
e089f05c | 46 | cow = btrfs_alloc_free_block(trans, root); |
e20d96d6 CM |
47 | cow_node = btrfs_buffer_node(cow); |
48 | memcpy(cow_node, btrfs_buffer_node(buf), root->blocksize); | |
49 | btrfs_set_header_blocknr(&cow_node->header, cow->b_blocknr); | |
02217ed2 | 50 | *cow_ret = cow; |
d5719762 | 51 | mark_buffer_dirty(cow); |
e089f05c | 52 | btrfs_inc_ref(trans, root, buf); |
02217ed2 CM |
53 | if (buf == root->node) { |
54 | root->node = cow; | |
e20d96d6 | 55 | get_bh(cow); |
a28ec197 | 56 | if (buf != root->commit_root) |
e20d96d6 | 57 | btrfs_free_extent(trans, root, buf->b_blocknr, 1, 1); |
234b63a0 | 58 | btrfs_block_release(root, buf); |
02217ed2 | 59 | } else { |
e20d96d6 CM |
60 | btrfs_set_node_blockptr(btrfs_buffer_node(parent), parent_slot, |
61 | cow->b_blocknr); | |
d5719762 | 62 | mark_buffer_dirty(parent); |
e20d96d6 | 63 | btrfs_free_extent(trans, root, buf->b_blocknr, 1, 1); |
02217ed2 | 64 | } |
234b63a0 | 65 | btrfs_block_release(root, buf); |
02217ed2 CM |
66 | return 0; |
67 | } | |
68 | ||
74123bd7 CM |
69 | /* |
70 | * The leaf data grows from end-to-front in the node. | |
71 | * this returns the address of the start of the last item, | |
72 | * which is the stop of the leaf data stack | |
73 | */ | |
123abc88 CM |
74 | static inline unsigned int leaf_data_end(struct btrfs_root *root, |
75 | struct btrfs_leaf *leaf) | |
be0e5c09 | 76 | { |
7518a238 | 77 | u32 nr = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 78 | if (nr == 0) |
123abc88 | 79 | return BTRFS_LEAF_DATA_SIZE(root); |
0783fcfc | 80 | return btrfs_item_offset(leaf->items + nr - 1); |
be0e5c09 CM |
81 | } |
82 | ||
74123bd7 CM |
83 | /* |
84 | * The space between the end of the leaf items and | |
85 | * the start of the leaf data. IOW, how much room | |
86 | * the leaf has left for both items and data | |
87 | */ | |
123abc88 | 88 | int btrfs_leaf_free_space(struct btrfs_root *root, struct btrfs_leaf *leaf) |
be0e5c09 | 89 | { |
123abc88 | 90 | int data_end = leaf_data_end(root, leaf); |
7518a238 | 91 | int nritems = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 92 | char *items_end = (char *)(leaf->items + nritems + 1); |
123abc88 | 93 | return (char *)(btrfs_leaf_data(leaf) + data_end) - (char *)items_end; |
be0e5c09 CM |
94 | } |
95 | ||
74123bd7 CM |
96 | /* |
97 | * compare two keys in a memcmp fashion | |
98 | */ | |
9aca1d51 | 99 | static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2) |
be0e5c09 | 100 | { |
e2fa7227 CM |
101 | struct btrfs_key k1; |
102 | ||
103 | btrfs_disk_key_to_cpu(&k1, disk); | |
104 | ||
105 | if (k1.objectid > k2->objectid) | |
be0e5c09 | 106 | return 1; |
e2fa7227 | 107 | if (k1.objectid < k2->objectid) |
be0e5c09 | 108 | return -1; |
62e2749e CM |
109 | if (k1.flags > k2->flags) |
110 | return 1; | |
111 | if (k1.flags < k2->flags) | |
112 | return -1; | |
a8a2ee0c CM |
113 | if (k1.offset > k2->offset) |
114 | return 1; | |
115 | if (k1.offset < k2->offset) | |
116 | return -1; | |
be0e5c09 CM |
117 | return 0; |
118 | } | |
74123bd7 | 119 | |
123abc88 CM |
120 | static int check_node(struct btrfs_root *root, struct btrfs_path *path, |
121 | int level) | |
aa5d6bed CM |
122 | { |
123 | int i; | |
234b63a0 | 124 | struct btrfs_node *parent = NULL; |
e20d96d6 | 125 | struct btrfs_node *node = btrfs_buffer_node(path->nodes[level]); |
aa5d6bed | 126 | int parent_slot; |
7518a238 | 127 | u32 nritems = btrfs_header_nritems(&node->header); |
aa5d6bed CM |
128 | |
129 | if (path->nodes[level + 1]) | |
e20d96d6 | 130 | parent = btrfs_buffer_node(path->nodes[level + 1]); |
aa5d6bed | 131 | parent_slot = path->slots[level + 1]; |
7518a238 CM |
132 | BUG_ON(nritems == 0); |
133 | if (parent) { | |
e2fa7227 | 134 | struct btrfs_disk_key *parent_key; |
123abc88 CM |
135 | parent_key = &parent->ptrs[parent_slot].key; |
136 | BUG_ON(memcmp(parent_key, &node->ptrs[0].key, | |
e2fa7227 | 137 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 138 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
7518a238 | 139 | btrfs_header_blocknr(&node->header)); |
aa5d6bed | 140 | } |
123abc88 | 141 | BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root)); |
7518a238 | 142 | for (i = 0; nritems > 1 && i < nritems - 2; i++) { |
e2fa7227 | 143 | struct btrfs_key cpukey; |
123abc88 CM |
144 | btrfs_disk_key_to_cpu(&cpukey, &node->ptrs[i + 1].key); |
145 | BUG_ON(comp_keys(&node->ptrs[i].key, &cpukey) >= 0); | |
aa5d6bed CM |
146 | } |
147 | return 0; | |
148 | } | |
149 | ||
123abc88 CM |
150 | static int check_leaf(struct btrfs_root *root, struct btrfs_path *path, |
151 | int level) | |
aa5d6bed CM |
152 | { |
153 | int i; | |
e20d96d6 | 154 | struct btrfs_leaf *leaf = btrfs_buffer_leaf(path->nodes[level]); |
234b63a0 | 155 | struct btrfs_node *parent = NULL; |
aa5d6bed | 156 | int parent_slot; |
7518a238 | 157 | u32 nritems = btrfs_header_nritems(&leaf->header); |
aa5d6bed CM |
158 | |
159 | if (path->nodes[level + 1]) | |
e20d96d6 | 160 | parent = btrfs_buffer_node(path->nodes[level + 1]); |
aa5d6bed | 161 | parent_slot = path->slots[level + 1]; |
123abc88 | 162 | BUG_ON(btrfs_leaf_free_space(root, leaf) < 0); |
7518a238 CM |
163 | |
164 | if (nritems == 0) | |
165 | return 0; | |
166 | ||
167 | if (parent) { | |
e2fa7227 | 168 | struct btrfs_disk_key *parent_key; |
123abc88 | 169 | parent_key = &parent->ptrs[parent_slot].key; |
aa5d6bed | 170 | BUG_ON(memcmp(parent_key, &leaf->items[0].key, |
e2fa7227 | 171 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 172 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
7518a238 | 173 | btrfs_header_blocknr(&leaf->header)); |
aa5d6bed | 174 | } |
7518a238 | 175 | for (i = 0; nritems > 1 && i < nritems - 2; i++) { |
e2fa7227 CM |
176 | struct btrfs_key cpukey; |
177 | btrfs_disk_key_to_cpu(&cpukey, &leaf->items[i + 1].key); | |
aa5d6bed | 178 | BUG_ON(comp_keys(&leaf->items[i].key, |
e2fa7227 | 179 | &cpukey) >= 0); |
0783fcfc CM |
180 | BUG_ON(btrfs_item_offset(leaf->items + i) != |
181 | btrfs_item_end(leaf->items + i + 1)); | |
aa5d6bed | 182 | if (i == 0) { |
0783fcfc CM |
183 | BUG_ON(btrfs_item_offset(leaf->items + i) + |
184 | btrfs_item_size(leaf->items + i) != | |
123abc88 | 185 | BTRFS_LEAF_DATA_SIZE(root)); |
aa5d6bed CM |
186 | } |
187 | } | |
aa5d6bed CM |
188 | return 0; |
189 | } | |
190 | ||
123abc88 CM |
191 | static int check_block(struct btrfs_root *root, struct btrfs_path *path, |
192 | int level) | |
aa5d6bed CM |
193 | { |
194 | if (level == 0) | |
123abc88 CM |
195 | return check_leaf(root, path, level); |
196 | return check_node(root, path, level); | |
aa5d6bed CM |
197 | } |
198 | ||
74123bd7 CM |
199 | /* |
200 | * search for key in the array p. items p are item_size apart | |
201 | * and there are 'max' items in p | |
202 | * the slot in the array is returned via slot, and it points to | |
203 | * the place where you would insert key if it is not found in | |
204 | * the array. | |
205 | * | |
206 | * slot may point to max if the key is bigger than all of the keys | |
207 | */ | |
9aca1d51 | 208 | static int generic_bin_search(char *p, int item_size, struct btrfs_key *key, |
be0e5c09 CM |
209 | int max, int *slot) |
210 | { | |
211 | int low = 0; | |
212 | int high = max; | |
213 | int mid; | |
214 | int ret; | |
e2fa7227 | 215 | struct btrfs_disk_key *tmp; |
be0e5c09 CM |
216 | |
217 | while(low < high) { | |
218 | mid = (low + high) / 2; | |
e2fa7227 | 219 | tmp = (struct btrfs_disk_key *)(p + mid * item_size); |
be0e5c09 CM |
220 | ret = comp_keys(tmp, key); |
221 | ||
222 | if (ret < 0) | |
223 | low = mid + 1; | |
224 | else if (ret > 0) | |
225 | high = mid; | |
226 | else { | |
227 | *slot = mid; | |
228 | return 0; | |
229 | } | |
230 | } | |
231 | *slot = low; | |
232 | return 1; | |
233 | } | |
234 | ||
97571fd0 CM |
235 | /* |
236 | * simple bin_search frontend that does the right thing for | |
237 | * leaves vs nodes | |
238 | */ | |
9aca1d51 | 239 | static int bin_search(struct btrfs_node *c, struct btrfs_key *key, int *slot) |
be0e5c09 | 240 | { |
7518a238 | 241 | if (btrfs_is_leaf(c)) { |
234b63a0 | 242 | struct btrfs_leaf *l = (struct btrfs_leaf *)c; |
0783fcfc CM |
243 | return generic_bin_search((void *)l->items, |
244 | sizeof(struct btrfs_item), | |
7518a238 CM |
245 | key, btrfs_header_nritems(&c->header), |
246 | slot); | |
be0e5c09 | 247 | } else { |
123abc88 CM |
248 | return generic_bin_search((void *)c->ptrs, |
249 | sizeof(struct btrfs_key_ptr), | |
7518a238 CM |
250 | key, btrfs_header_nritems(&c->header), |
251 | slot); | |
be0e5c09 CM |
252 | } |
253 | return -1; | |
254 | } | |
255 | ||
e20d96d6 CM |
256 | static struct buffer_head *read_node_slot(struct btrfs_root *root, |
257 | struct buffer_head *parent_buf, | |
bb803951 CM |
258 | int slot) |
259 | { | |
e20d96d6 | 260 | struct btrfs_node *node = btrfs_buffer_node(parent_buf); |
bb803951 CM |
261 | if (slot < 0) |
262 | return NULL; | |
7518a238 | 263 | if (slot >= btrfs_header_nritems(&node->header)) |
bb803951 | 264 | return NULL; |
1d4f8a0c | 265 | return read_tree_block(root, btrfs_node_blockptr(node, slot)); |
bb803951 CM |
266 | } |
267 | ||
e089f05c CM |
268 | static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root |
269 | *root, struct btrfs_path *path, int level) | |
bb803951 | 270 | { |
e20d96d6 CM |
271 | struct buffer_head *right_buf; |
272 | struct buffer_head *mid_buf; | |
273 | struct buffer_head *left_buf; | |
274 | struct buffer_head *parent_buf = NULL; | |
234b63a0 CM |
275 | struct btrfs_node *right = NULL; |
276 | struct btrfs_node *mid; | |
277 | struct btrfs_node *left = NULL; | |
278 | struct btrfs_node *parent = NULL; | |
bb803951 CM |
279 | int ret = 0; |
280 | int wret; | |
281 | int pslot; | |
bb803951 | 282 | int orig_slot = path->slots[level]; |
79f95c82 | 283 | u64 orig_ptr; |
bb803951 CM |
284 | |
285 | if (level == 0) | |
286 | return 0; | |
287 | ||
288 | mid_buf = path->nodes[level]; | |
e20d96d6 | 289 | mid = btrfs_buffer_node(mid_buf); |
1d4f8a0c | 290 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
79f95c82 | 291 | |
234b63a0 | 292 | if (level < BTRFS_MAX_LEVEL - 1) |
bb803951 CM |
293 | parent_buf = path->nodes[level + 1]; |
294 | pslot = path->slots[level + 1]; | |
295 | ||
40689478 CM |
296 | /* |
297 | * deal with the case where there is only one pointer in the root | |
298 | * by promoting the node below to a root | |
299 | */ | |
bb803951 | 300 | if (!parent_buf) { |
e20d96d6 CM |
301 | struct buffer_head *child; |
302 | u64 blocknr = mid_buf->b_blocknr; | |
bb803951 | 303 | |
7518a238 | 304 | if (btrfs_header_nritems(&mid->header) != 1) |
bb803951 CM |
305 | return 0; |
306 | ||
307 | /* promote the child to a root */ | |
308 | child = read_node_slot(root, mid_buf, 0); | |
309 | BUG_ON(!child); | |
310 | root->node = child; | |
311 | path->nodes[level] = NULL; | |
312 | /* once for the path */ | |
234b63a0 | 313 | btrfs_block_release(root, mid_buf); |
bb803951 | 314 | /* once for the root ptr */ |
234b63a0 | 315 | btrfs_block_release(root, mid_buf); |
e089f05c CM |
316 | clean_tree_block(trans, root, mid_buf); |
317 | return btrfs_free_extent(trans, root, blocknr, 1, 1); | |
bb803951 | 318 | } |
e20d96d6 | 319 | parent = btrfs_buffer_node(parent_buf); |
bb803951 | 320 | |
123abc88 CM |
321 | if (btrfs_header_nritems(&mid->header) > |
322 | BTRFS_NODEPTRS_PER_BLOCK(root) / 4) | |
bb803951 CM |
323 | return 0; |
324 | ||
bb803951 CM |
325 | left_buf = read_node_slot(root, parent_buf, pslot - 1); |
326 | right_buf = read_node_slot(root, parent_buf, pslot + 1); | |
79f95c82 CM |
327 | |
328 | /* first, try to make some room in the middle buffer */ | |
bb803951 | 329 | if (left_buf) { |
e089f05c CM |
330 | btrfs_cow_block(trans, root, left_buf, parent_buf, pslot - 1, |
331 | &left_buf); | |
e20d96d6 | 332 | left = btrfs_buffer_node(left_buf); |
7518a238 | 333 | orig_slot += btrfs_header_nritems(&left->header); |
e089f05c | 334 | wret = push_node_left(trans, root, left_buf, mid_buf); |
79f95c82 CM |
335 | if (wret < 0) |
336 | ret = wret; | |
bb803951 | 337 | } |
79f95c82 CM |
338 | |
339 | /* | |
340 | * then try to empty the right most buffer into the middle | |
341 | */ | |
bb803951 | 342 | if (right_buf) { |
e089f05c CM |
343 | btrfs_cow_block(trans, root, right_buf, parent_buf, pslot + 1, |
344 | &right_buf); | |
e20d96d6 | 345 | right = btrfs_buffer_node(right_buf); |
e089f05c | 346 | wret = push_node_left(trans, root, mid_buf, right_buf); |
79f95c82 CM |
347 | if (wret < 0) |
348 | ret = wret; | |
7518a238 | 349 | if (btrfs_header_nritems(&right->header) == 0) { |
e20d96d6 | 350 | u64 blocknr = right_buf->b_blocknr; |
234b63a0 | 351 | btrfs_block_release(root, right_buf); |
e089f05c | 352 | clean_tree_block(trans, root, right_buf); |
bb803951 CM |
353 | right_buf = NULL; |
354 | right = NULL; | |
e089f05c CM |
355 | wret = del_ptr(trans, root, path, level + 1, pslot + |
356 | 1); | |
bb803951 CM |
357 | if (wret) |
358 | ret = wret; | |
e089f05c | 359 | wret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 CM |
360 | if (wret) |
361 | ret = wret; | |
362 | } else { | |
123abc88 CM |
363 | memcpy(&parent->ptrs[pslot + 1].key, |
364 | &right->ptrs[0].key, | |
e2fa7227 | 365 | sizeof(struct btrfs_disk_key)); |
d5719762 | 366 | mark_buffer_dirty(parent_buf); |
bb803951 CM |
367 | } |
368 | } | |
7518a238 | 369 | if (btrfs_header_nritems(&mid->header) == 1) { |
79f95c82 CM |
370 | /* |
371 | * we're not allowed to leave a node with one item in the | |
372 | * tree during a delete. A deletion from lower in the tree | |
373 | * could try to delete the only pointer in this node. | |
374 | * So, pull some keys from the left. | |
375 | * There has to be a left pointer at this point because | |
376 | * otherwise we would have pulled some pointers from the | |
377 | * right | |
378 | */ | |
379 | BUG_ON(!left_buf); | |
e089f05c | 380 | wret = balance_node_right(trans, root, mid_buf, left_buf); |
79f95c82 CM |
381 | if (wret < 0) |
382 | ret = wret; | |
383 | BUG_ON(wret == 1); | |
384 | } | |
7518a238 | 385 | if (btrfs_header_nritems(&mid->header) == 0) { |
79f95c82 | 386 | /* we've managed to empty the middle node, drop it */ |
e20d96d6 | 387 | u64 blocknr = mid_buf->b_blocknr; |
234b63a0 | 388 | btrfs_block_release(root, mid_buf); |
e089f05c | 389 | clean_tree_block(trans, root, mid_buf); |
bb803951 CM |
390 | mid_buf = NULL; |
391 | mid = NULL; | |
e089f05c | 392 | wret = del_ptr(trans, root, path, level + 1, pslot); |
bb803951 CM |
393 | if (wret) |
394 | ret = wret; | |
e089f05c | 395 | wret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 CM |
396 | if (wret) |
397 | ret = wret; | |
79f95c82 CM |
398 | } else { |
399 | /* update the parent key to reflect our changes */ | |
123abc88 | 400 | memcpy(&parent->ptrs[pslot].key, &mid->ptrs[0].key, |
e2fa7227 | 401 | sizeof(struct btrfs_disk_key)); |
d5719762 | 402 | mark_buffer_dirty(parent_buf); |
79f95c82 | 403 | } |
bb803951 | 404 | |
79f95c82 | 405 | /* update the path */ |
bb803951 | 406 | if (left_buf) { |
7518a238 | 407 | if (btrfs_header_nritems(&left->header) > orig_slot) { |
e20d96d6 | 408 | get_bh(left_buf); |
bb803951 CM |
409 | path->nodes[level] = left_buf; |
410 | path->slots[level + 1] -= 1; | |
411 | path->slots[level] = orig_slot; | |
412 | if (mid_buf) | |
234b63a0 | 413 | btrfs_block_release(root, mid_buf); |
bb803951 | 414 | } else { |
7518a238 | 415 | orig_slot -= btrfs_header_nritems(&left->header); |
bb803951 CM |
416 | path->slots[level] = orig_slot; |
417 | } | |
418 | } | |
79f95c82 | 419 | /* double check we haven't messed things up */ |
123abc88 | 420 | check_block(root, path, level); |
e20d96d6 CM |
421 | if (orig_ptr != |
422 | btrfs_node_blockptr(btrfs_buffer_node(path->nodes[level]), | |
423 | path->slots[level])) | |
79f95c82 | 424 | BUG(); |
bb803951 CM |
425 | |
426 | if (right_buf) | |
234b63a0 | 427 | btrfs_block_release(root, right_buf); |
bb803951 | 428 | if (left_buf) |
234b63a0 | 429 | btrfs_block_release(root, left_buf); |
bb803951 CM |
430 | return ret; |
431 | } | |
432 | ||
74123bd7 CM |
433 | /* |
434 | * look for key in the tree. path is filled in with nodes along the way | |
435 | * if key is found, we return zero and you can find the item in the leaf | |
436 | * level of the path (level 0) | |
437 | * | |
438 | * If the key isn't found, the path points to the slot where it should | |
aa5d6bed CM |
439 | * be inserted, and 1 is returned. If there are other errors during the |
440 | * search a negative error number is returned. | |
97571fd0 CM |
441 | * |
442 | * if ins_len > 0, nodes and leaves will be split as we walk down the | |
443 | * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if | |
444 | * possible) | |
74123bd7 | 445 | */ |
e089f05c CM |
446 | int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root |
447 | *root, struct btrfs_key *key, struct btrfs_path *p, int | |
448 | ins_len, int cow) | |
be0e5c09 | 449 | { |
e20d96d6 CM |
450 | struct buffer_head *b; |
451 | struct buffer_head *cow_buf; | |
234b63a0 | 452 | struct btrfs_node *c; |
be0e5c09 CM |
453 | int slot; |
454 | int ret; | |
455 | int level; | |
5c680ed6 | 456 | |
bb803951 CM |
457 | again: |
458 | b = root->node; | |
e20d96d6 | 459 | get_bh(b); |
eb60ceac | 460 | while (b) { |
e20d96d6 CM |
461 | c = btrfs_buffer_node(b); |
462 | level = btrfs_header_level(&c->header); | |
02217ed2 CM |
463 | if (cow) { |
464 | int wret; | |
e20d96d6 CM |
465 | wret = btrfs_cow_block(trans, root, b, |
466 | p->nodes[level + 1], | |
467 | p->slots[level + 1], | |
e089f05c | 468 | &cow_buf); |
02217ed2 CM |
469 | b = cow_buf; |
470 | } | |
471 | BUG_ON(!cow && ins_len); | |
e20d96d6 | 472 | c = btrfs_buffer_node(b); |
eb60ceac | 473 | p->nodes[level] = b; |
123abc88 | 474 | ret = check_block(root, p, level); |
aa5d6bed CM |
475 | if (ret) |
476 | return -1; | |
be0e5c09 | 477 | ret = bin_search(c, key, &slot); |
7518a238 | 478 | if (!btrfs_is_leaf(c)) { |
be0e5c09 CM |
479 | if (ret && slot > 0) |
480 | slot -= 1; | |
481 | p->slots[level] = slot; | |
7518a238 | 482 | if (ins_len > 0 && btrfs_header_nritems(&c->header) == |
123abc88 | 483 | BTRFS_NODEPTRS_PER_BLOCK(root)) { |
e089f05c | 484 | int sret = split_node(trans, root, p, level); |
5c680ed6 CM |
485 | BUG_ON(sret > 0); |
486 | if (sret) | |
487 | return sret; | |
488 | b = p->nodes[level]; | |
e20d96d6 | 489 | c = btrfs_buffer_node(b); |
5c680ed6 | 490 | slot = p->slots[level]; |
bb803951 | 491 | } else if (ins_len < 0) { |
e089f05c CM |
492 | int sret = balance_level(trans, root, p, |
493 | level); | |
bb803951 CM |
494 | if (sret) |
495 | return sret; | |
496 | b = p->nodes[level]; | |
497 | if (!b) | |
498 | goto again; | |
e20d96d6 | 499 | c = btrfs_buffer_node(b); |
bb803951 | 500 | slot = p->slots[level]; |
7518a238 | 501 | BUG_ON(btrfs_header_nritems(&c->header) == 1); |
5c680ed6 | 502 | } |
1d4f8a0c | 503 | b = read_tree_block(root, btrfs_node_blockptr(c, slot)); |
be0e5c09 | 504 | } else { |
234b63a0 | 505 | struct btrfs_leaf *l = (struct btrfs_leaf *)c; |
be0e5c09 | 506 | p->slots[level] = slot; |
123abc88 | 507 | if (ins_len > 0 && btrfs_leaf_free_space(root, l) < |
0783fcfc | 508 | sizeof(struct btrfs_item) + ins_len) { |
e089f05c | 509 | int sret = split_leaf(trans, root, p, ins_len); |
5c680ed6 CM |
510 | BUG_ON(sret > 0); |
511 | if (sret) | |
512 | return sret; | |
513 | } | |
be0e5c09 CM |
514 | return ret; |
515 | } | |
516 | } | |
aa5d6bed | 517 | return 1; |
be0e5c09 CM |
518 | } |
519 | ||
74123bd7 CM |
520 | /* |
521 | * adjust the pointers going up the tree, starting at level | |
522 | * making sure the right key of each node is points to 'key'. | |
523 | * This is used after shifting pointers to the left, so it stops | |
524 | * fixing up pointers when a given leaf/node is not in slot 0 of the | |
525 | * higher levels | |
aa5d6bed CM |
526 | * |
527 | * If this fails to write a tree block, it returns -1, but continues | |
528 | * fixing up the blocks in ram so the tree is consistent. | |
74123bd7 | 529 | */ |
e089f05c CM |
530 | static int fixup_low_keys(struct btrfs_trans_handle *trans, struct btrfs_root |
531 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
532 | *key, int level) | |
be0e5c09 CM |
533 | { |
534 | int i; | |
aa5d6bed | 535 | int ret = 0; |
234b63a0 CM |
536 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
537 | struct btrfs_node *t; | |
be0e5c09 | 538 | int tslot = path->slots[i]; |
eb60ceac | 539 | if (!path->nodes[i]) |
be0e5c09 | 540 | break; |
e20d96d6 | 541 | t = btrfs_buffer_node(path->nodes[i]); |
123abc88 | 542 | memcpy(&t->ptrs[tslot].key, key, sizeof(*key)); |
d5719762 | 543 | mark_buffer_dirty(path->nodes[i]); |
be0e5c09 CM |
544 | if (tslot != 0) |
545 | break; | |
546 | } | |
aa5d6bed | 547 | return ret; |
be0e5c09 CM |
548 | } |
549 | ||
74123bd7 CM |
550 | /* |
551 | * try to push data from one node into the next node left in the | |
79f95c82 | 552 | * tree. |
aa5d6bed CM |
553 | * |
554 | * returns 0 if some ptrs were pushed left, < 0 if there was some horrible | |
555 | * error, and > 0 if there was no room in the left hand block. | |
74123bd7 | 556 | */ |
e089f05c | 557 | static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root |
e20d96d6 CM |
558 | *root, struct buffer_head *dst_buf, struct |
559 | buffer_head *src_buf) | |
be0e5c09 | 560 | { |
e20d96d6 CM |
561 | struct btrfs_node *src = btrfs_buffer_node(src_buf); |
562 | struct btrfs_node *dst = btrfs_buffer_node(dst_buf); | |
be0e5c09 | 563 | int push_items = 0; |
bb803951 CM |
564 | int src_nritems; |
565 | int dst_nritems; | |
aa5d6bed | 566 | int ret = 0; |
be0e5c09 | 567 | |
7518a238 CM |
568 | src_nritems = btrfs_header_nritems(&src->header); |
569 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 570 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
eb60ceac | 571 | if (push_items <= 0) { |
be0e5c09 | 572 | return 1; |
eb60ceac | 573 | } |
be0e5c09 | 574 | |
bb803951 | 575 | if (src_nritems < push_items) |
79f95c82 CM |
576 | push_items = src_nritems; |
577 | ||
123abc88 CM |
578 | memcpy(dst->ptrs + dst_nritems, src->ptrs, |
579 | push_items * sizeof(struct btrfs_key_ptr)); | |
bb803951 | 580 | if (push_items < src_nritems) { |
123abc88 | 581 | memmove(src->ptrs, src->ptrs + push_items, |
e2fa7227 | 582 | (src_nritems - push_items) * |
123abc88 | 583 | sizeof(struct btrfs_key_ptr)); |
bb803951 | 584 | } |
7518a238 CM |
585 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
586 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
d5719762 CM |
587 | mark_buffer_dirty(src_buf); |
588 | mark_buffer_dirty(dst_buf); | |
79f95c82 CM |
589 | return ret; |
590 | } | |
591 | ||
592 | /* | |
593 | * try to push data from one node into the next node right in the | |
594 | * tree. | |
595 | * | |
596 | * returns 0 if some ptrs were pushed, < 0 if there was some horrible | |
597 | * error, and > 0 if there was no room in the right hand block. | |
598 | * | |
599 | * this will only push up to 1/2 the contents of the left node over | |
600 | */ | |
e089f05c | 601 | static int balance_node_right(struct btrfs_trans_handle *trans, struct |
e20d96d6 CM |
602 | btrfs_root *root, struct buffer_head *dst_buf, |
603 | struct buffer_head *src_buf) | |
79f95c82 | 604 | { |
e20d96d6 CM |
605 | struct btrfs_node *src = btrfs_buffer_node(src_buf); |
606 | struct btrfs_node *dst = btrfs_buffer_node(dst_buf); | |
79f95c82 CM |
607 | int push_items = 0; |
608 | int max_push; | |
609 | int src_nritems; | |
610 | int dst_nritems; | |
611 | int ret = 0; | |
79f95c82 | 612 | |
7518a238 CM |
613 | src_nritems = btrfs_header_nritems(&src->header); |
614 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 615 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
79f95c82 CM |
616 | if (push_items <= 0) { |
617 | return 1; | |
618 | } | |
619 | ||
620 | max_push = src_nritems / 2 + 1; | |
621 | /* don't try to empty the node */ | |
622 | if (max_push > src_nritems) | |
623 | return 1; | |
624 | if (max_push < push_items) | |
625 | push_items = max_push; | |
626 | ||
123abc88 CM |
627 | memmove(dst->ptrs + push_items, dst->ptrs, |
628 | dst_nritems * sizeof(struct btrfs_key_ptr)); | |
629 | memcpy(dst->ptrs, src->ptrs + src_nritems - push_items, | |
630 | push_items * sizeof(struct btrfs_key_ptr)); | |
79f95c82 | 631 | |
7518a238 CM |
632 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
633 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
79f95c82 | 634 | |
d5719762 CM |
635 | mark_buffer_dirty(src_buf); |
636 | mark_buffer_dirty(dst_buf); | |
aa5d6bed | 637 | return ret; |
be0e5c09 CM |
638 | } |
639 | ||
97571fd0 CM |
640 | /* |
641 | * helper function to insert a new root level in the tree. | |
642 | * A new node is allocated, and a single item is inserted to | |
643 | * point to the existing root | |
aa5d6bed CM |
644 | * |
645 | * returns zero on success or < 0 on failure. | |
97571fd0 | 646 | */ |
e089f05c CM |
647 | static int insert_new_root(struct btrfs_trans_handle *trans, struct btrfs_root |
648 | *root, struct btrfs_path *path, int level) | |
5c680ed6 | 649 | { |
e20d96d6 | 650 | struct buffer_head *t; |
234b63a0 CM |
651 | struct btrfs_node *lower; |
652 | struct btrfs_node *c; | |
e2fa7227 | 653 | struct btrfs_disk_key *lower_key; |
5c680ed6 CM |
654 | |
655 | BUG_ON(path->nodes[level]); | |
656 | BUG_ON(path->nodes[level-1] != root->node); | |
657 | ||
e089f05c | 658 | t = btrfs_alloc_free_block(trans, root); |
e20d96d6 | 659 | c = btrfs_buffer_node(t); |
123abc88 | 660 | memset(c, 0, root->blocksize); |
7518a238 CM |
661 | btrfs_set_header_nritems(&c->header, 1); |
662 | btrfs_set_header_level(&c->header, level); | |
e20d96d6 | 663 | btrfs_set_header_blocknr(&c->header, t->b_blocknr); |
7518a238 | 664 | btrfs_set_header_parentid(&c->header, |
e20d96d6 CM |
665 | btrfs_header_parentid(btrfs_buffer_header(root->node))); |
666 | lower = btrfs_buffer_node(path->nodes[level-1]); | |
7518a238 | 667 | if (btrfs_is_leaf(lower)) |
234b63a0 | 668 | lower_key = &((struct btrfs_leaf *)lower)->items[0].key; |
5c680ed6 | 669 | else |
123abc88 CM |
670 | lower_key = &lower->ptrs[0].key; |
671 | memcpy(&c->ptrs[0].key, lower_key, sizeof(struct btrfs_disk_key)); | |
e20d96d6 | 672 | btrfs_set_node_blockptr(c, 0, path->nodes[level - 1]->b_blocknr); |
d5719762 CM |
673 | |
674 | mark_buffer_dirty(t); | |
675 | ||
5c680ed6 | 676 | /* the super has an extra ref to root->node */ |
234b63a0 | 677 | btrfs_block_release(root, root->node); |
5c680ed6 | 678 | root->node = t; |
e20d96d6 | 679 | get_bh(t); |
5c680ed6 CM |
680 | path->nodes[level] = t; |
681 | path->slots[level] = 0; | |
682 | return 0; | |
683 | } | |
684 | ||
74123bd7 CM |
685 | /* |
686 | * worker function to insert a single pointer in a node. | |
687 | * the node should have enough room for the pointer already | |
97571fd0 | 688 | * |
74123bd7 CM |
689 | * slot and level indicate where you want the key to go, and |
690 | * blocknr is the block the key points to. | |
aa5d6bed CM |
691 | * |
692 | * returns zero on success and < 0 on any error | |
74123bd7 | 693 | */ |
e089f05c CM |
694 | static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root |
695 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
696 | *key, u64 blocknr, int slot, int level) | |
74123bd7 | 697 | { |
234b63a0 | 698 | struct btrfs_node *lower; |
74123bd7 | 699 | int nritems; |
5c680ed6 CM |
700 | |
701 | BUG_ON(!path->nodes[level]); | |
e20d96d6 | 702 | lower = btrfs_buffer_node(path->nodes[level]); |
7518a238 | 703 | nritems = btrfs_header_nritems(&lower->header); |
74123bd7 CM |
704 | if (slot > nritems) |
705 | BUG(); | |
123abc88 | 706 | if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root)) |
74123bd7 CM |
707 | BUG(); |
708 | if (slot != nritems) { | |
123abc88 CM |
709 | memmove(lower->ptrs + slot + 1, lower->ptrs + slot, |
710 | (nritems - slot) * sizeof(struct btrfs_key_ptr)); | |
74123bd7 | 711 | } |
123abc88 | 712 | memcpy(&lower->ptrs[slot].key, key, sizeof(struct btrfs_disk_key)); |
1d4f8a0c | 713 | btrfs_set_node_blockptr(lower, slot, blocknr); |
7518a238 | 714 | btrfs_set_header_nritems(&lower->header, nritems + 1); |
d5719762 | 715 | mark_buffer_dirty(path->nodes[level]); |
74123bd7 CM |
716 | return 0; |
717 | } | |
718 | ||
97571fd0 CM |
719 | /* |
720 | * split the node at the specified level in path in two. | |
721 | * The path is corrected to point to the appropriate node after the split | |
722 | * | |
723 | * Before splitting this tries to make some room in the node by pushing | |
724 | * left and right, if either one works, it returns right away. | |
aa5d6bed CM |
725 | * |
726 | * returns 0 on success and < 0 on failure | |
97571fd0 | 727 | */ |
e089f05c CM |
728 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
729 | *root, struct btrfs_path *path, int level) | |
be0e5c09 | 730 | { |
e20d96d6 | 731 | struct buffer_head *t; |
234b63a0 | 732 | struct btrfs_node *c; |
e20d96d6 | 733 | struct buffer_head *split_buffer; |
234b63a0 | 734 | struct btrfs_node *split; |
be0e5c09 | 735 | int mid; |
5c680ed6 | 736 | int ret; |
aa5d6bed | 737 | int wret; |
7518a238 | 738 | u32 c_nritems; |
eb60ceac | 739 | |
5c680ed6 | 740 | t = path->nodes[level]; |
e20d96d6 | 741 | c = btrfs_buffer_node(t); |
5c680ed6 CM |
742 | if (t == root->node) { |
743 | /* trying to split the root, lets make a new one */ | |
e089f05c | 744 | ret = insert_new_root(trans, root, path, level + 1); |
5c680ed6 CM |
745 | if (ret) |
746 | return ret; | |
be0e5c09 | 747 | } |
7518a238 | 748 | c_nritems = btrfs_header_nritems(&c->header); |
e089f05c | 749 | split_buffer = btrfs_alloc_free_block(trans, root); |
e20d96d6 | 750 | split = btrfs_buffer_node(split_buffer); |
7518a238 | 751 | btrfs_set_header_flags(&split->header, btrfs_header_flags(&c->header)); |
e20d96d6 | 752 | btrfs_set_header_blocknr(&split->header, split_buffer->b_blocknr); |
7518a238 | 753 | btrfs_set_header_parentid(&split->header, |
e20d96d6 | 754 | btrfs_header_parentid(btrfs_buffer_header(root->node))); |
7518a238 | 755 | mid = (c_nritems + 1) / 2; |
123abc88 CM |
756 | memcpy(split->ptrs, c->ptrs + mid, |
757 | (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); | |
7518a238 CM |
758 | btrfs_set_header_nritems(&split->header, c_nritems - mid); |
759 | btrfs_set_header_nritems(&c->header, mid); | |
aa5d6bed CM |
760 | ret = 0; |
761 | ||
d5719762 CM |
762 | mark_buffer_dirty(t); |
763 | mark_buffer_dirty(split_buffer); | |
e089f05c | 764 | wret = insert_ptr(trans, root, path, &split->ptrs[0].key, |
e20d96d6 | 765 | split_buffer->b_blocknr, path->slots[level + 1] + 1, |
123abc88 | 766 | level + 1); |
aa5d6bed CM |
767 | if (wret) |
768 | ret = wret; | |
769 | ||
5de08d7d | 770 | if (path->slots[level] >= mid) { |
5c680ed6 | 771 | path->slots[level] -= mid; |
234b63a0 | 772 | btrfs_block_release(root, t); |
5c680ed6 CM |
773 | path->nodes[level] = split_buffer; |
774 | path->slots[level + 1] += 1; | |
775 | } else { | |
234b63a0 | 776 | btrfs_block_release(root, split_buffer); |
be0e5c09 | 777 | } |
aa5d6bed | 778 | return ret; |
be0e5c09 CM |
779 | } |
780 | ||
74123bd7 CM |
781 | /* |
782 | * how many bytes are required to store the items in a leaf. start | |
783 | * and nr indicate which items in the leaf to check. This totals up the | |
784 | * space used both by the item structs and the item data | |
785 | */ | |
234b63a0 | 786 | static int leaf_space_used(struct btrfs_leaf *l, int start, int nr) |
be0e5c09 CM |
787 | { |
788 | int data_len; | |
789 | int end = start + nr - 1; | |
790 | ||
791 | if (!nr) | |
792 | return 0; | |
0783fcfc CM |
793 | data_len = btrfs_item_end(l->items + start); |
794 | data_len = data_len - btrfs_item_offset(l->items + end); | |
795 | data_len += sizeof(struct btrfs_item) * nr; | |
be0e5c09 CM |
796 | return data_len; |
797 | } | |
798 | ||
00ec4c51 CM |
799 | /* |
800 | * push some data in the path leaf to the right, trying to free up at | |
801 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
aa5d6bed CM |
802 | * |
803 | * returns 1 if the push failed because the other node didn't have enough | |
804 | * room, 0 if everything worked out and < 0 if there were major errors. | |
00ec4c51 | 805 | */ |
e089f05c CM |
806 | static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root |
807 | *root, struct btrfs_path *path, int data_size) | |
00ec4c51 | 808 | { |
e20d96d6 CM |
809 | struct buffer_head *left_buf = path->nodes[0]; |
810 | struct btrfs_leaf *left = btrfs_buffer_leaf(left_buf); | |
234b63a0 | 811 | struct btrfs_leaf *right; |
e20d96d6 CM |
812 | struct buffer_head *right_buf; |
813 | struct buffer_head *upper; | |
814 | struct btrfs_node *upper_node; | |
00ec4c51 CM |
815 | int slot; |
816 | int i; | |
817 | int free_space; | |
818 | int push_space = 0; | |
819 | int push_items = 0; | |
0783fcfc | 820 | struct btrfs_item *item; |
7518a238 CM |
821 | u32 left_nritems; |
822 | u32 right_nritems; | |
00ec4c51 CM |
823 | |
824 | slot = path->slots[1]; | |
825 | if (!path->nodes[1]) { | |
826 | return 1; | |
827 | } | |
828 | upper = path->nodes[1]; | |
e20d96d6 CM |
829 | upper_node = btrfs_buffer_node(upper); |
830 | if (slot >= btrfs_header_nritems(&upper_node->header) - 1) { | |
00ec4c51 CM |
831 | return 1; |
832 | } | |
e20d96d6 CM |
833 | right_buf = read_tree_block(root, |
834 | btrfs_node_blockptr(btrfs_buffer_node(upper), slot + 1)); | |
835 | right = btrfs_buffer_leaf(right_buf); | |
123abc88 | 836 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 837 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 838 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
839 | return 1; |
840 | } | |
02217ed2 | 841 | /* cow and double check */ |
e089f05c | 842 | btrfs_cow_block(trans, root, right_buf, upper, slot + 1, &right_buf); |
e20d96d6 | 843 | right = btrfs_buffer_leaf(right_buf); |
123abc88 | 844 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 845 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 846 | btrfs_block_release(root, right_buf); |
02217ed2 CM |
847 | return 1; |
848 | } | |
849 | ||
7518a238 CM |
850 | left_nritems = btrfs_header_nritems(&left->header); |
851 | for (i = left_nritems - 1; i >= 0; i--) { | |
00ec4c51 CM |
852 | item = left->items + i; |
853 | if (path->slots[0] == i) | |
854 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
855 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
856 | free_space) | |
00ec4c51 CM |
857 | break; |
858 | push_items++; | |
0783fcfc | 859 | push_space += btrfs_item_size(item) + sizeof(*item); |
00ec4c51 CM |
860 | } |
861 | if (push_items == 0) { | |
234b63a0 | 862 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
863 | return 1; |
864 | } | |
7518a238 | 865 | right_nritems = btrfs_header_nritems(&right->header); |
00ec4c51 | 866 | /* push left to right */ |
0783fcfc | 867 | push_space = btrfs_item_end(left->items + left_nritems - push_items); |
123abc88 | 868 | push_space -= leaf_data_end(root, left); |
00ec4c51 | 869 | /* make room in the right data area */ |
123abc88 CM |
870 | memmove(btrfs_leaf_data(right) + leaf_data_end(root, right) - |
871 | push_space, btrfs_leaf_data(right) + leaf_data_end(root, right), | |
872 | BTRFS_LEAF_DATA_SIZE(root) - leaf_data_end(root, right)); | |
00ec4c51 | 873 | /* copy from the left data area */ |
123abc88 CM |
874 | memcpy(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - push_space, |
875 | btrfs_leaf_data(left) + leaf_data_end(root, left), push_space); | |
00ec4c51 | 876 | memmove(right->items + push_items, right->items, |
0783fcfc | 877 | right_nritems * sizeof(struct btrfs_item)); |
00ec4c51 | 878 | /* copy the items from left to right */ |
7518a238 | 879 | memcpy(right->items, left->items + left_nritems - push_items, |
0783fcfc | 880 | push_items * sizeof(struct btrfs_item)); |
00ec4c51 CM |
881 | |
882 | /* update the item pointers */ | |
7518a238 CM |
883 | right_nritems += push_items; |
884 | btrfs_set_header_nritems(&right->header, right_nritems); | |
123abc88 | 885 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
7518a238 | 886 | for (i = 0; i < right_nritems; i++) { |
0783fcfc CM |
887 | btrfs_set_item_offset(right->items + i, push_space - |
888 | btrfs_item_size(right->items + i)); | |
889 | push_space = btrfs_item_offset(right->items + i); | |
00ec4c51 | 890 | } |
7518a238 CM |
891 | left_nritems -= push_items; |
892 | btrfs_set_header_nritems(&left->header, left_nritems); | |
00ec4c51 | 893 | |
d5719762 CM |
894 | mark_buffer_dirty(left_buf); |
895 | mark_buffer_dirty(right_buf); | |
e20d96d6 | 896 | memcpy(&upper_node->ptrs[slot + 1].key, |
e2fa7227 | 897 | &right->items[0].key, sizeof(struct btrfs_disk_key)); |
d5719762 | 898 | mark_buffer_dirty(upper); |
02217ed2 | 899 | |
00ec4c51 | 900 | /* then fixup the leaf pointer in the path */ |
7518a238 CM |
901 | if (path->slots[0] >= left_nritems) { |
902 | path->slots[0] -= left_nritems; | |
234b63a0 | 903 | btrfs_block_release(root, path->nodes[0]); |
00ec4c51 CM |
904 | path->nodes[0] = right_buf; |
905 | path->slots[1] += 1; | |
906 | } else { | |
234b63a0 | 907 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
908 | } |
909 | return 0; | |
910 | } | |
74123bd7 CM |
911 | /* |
912 | * push some data in the path leaf to the left, trying to free up at | |
913 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
914 | */ | |
e089f05c CM |
915 | static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root |
916 | *root, struct btrfs_path *path, int data_size) | |
be0e5c09 | 917 | { |
e20d96d6 CM |
918 | struct buffer_head *right_buf = path->nodes[0]; |
919 | struct btrfs_leaf *right = btrfs_buffer_leaf(right_buf); | |
920 | struct buffer_head *t; | |
234b63a0 | 921 | struct btrfs_leaf *left; |
be0e5c09 CM |
922 | int slot; |
923 | int i; | |
924 | int free_space; | |
925 | int push_space = 0; | |
926 | int push_items = 0; | |
0783fcfc | 927 | struct btrfs_item *item; |
7518a238 | 928 | u32 old_left_nritems; |
aa5d6bed CM |
929 | int ret = 0; |
930 | int wret; | |
be0e5c09 CM |
931 | |
932 | slot = path->slots[1]; | |
933 | if (slot == 0) { | |
934 | return 1; | |
935 | } | |
936 | if (!path->nodes[1]) { | |
937 | return 1; | |
938 | } | |
e20d96d6 CM |
939 | t = read_tree_block(root, |
940 | btrfs_node_blockptr(btrfs_buffer_node(path->nodes[1]), slot - 1)); | |
941 | left = btrfs_buffer_leaf(t); | |
123abc88 | 942 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 943 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 944 | btrfs_block_release(root, t); |
be0e5c09 CM |
945 | return 1; |
946 | } | |
02217ed2 CM |
947 | |
948 | /* cow and double check */ | |
e089f05c | 949 | btrfs_cow_block(trans, root, t, path->nodes[1], slot - 1, &t); |
e20d96d6 | 950 | left = btrfs_buffer_leaf(t); |
123abc88 | 951 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 952 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 953 | btrfs_block_release(root, t); |
02217ed2 CM |
954 | return 1; |
955 | } | |
956 | ||
7518a238 | 957 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
be0e5c09 CM |
958 | item = right->items + i; |
959 | if (path->slots[0] == i) | |
960 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
961 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
962 | free_space) | |
be0e5c09 CM |
963 | break; |
964 | push_items++; | |
0783fcfc | 965 | push_space += btrfs_item_size(item) + sizeof(*item); |
be0e5c09 CM |
966 | } |
967 | if (push_items == 0) { | |
234b63a0 | 968 | btrfs_block_release(root, t); |
be0e5c09 CM |
969 | return 1; |
970 | } | |
971 | /* push data from right to left */ | |
7518a238 | 972 | memcpy(left->items + btrfs_header_nritems(&left->header), |
0783fcfc | 973 | right->items, push_items * sizeof(struct btrfs_item)); |
123abc88 | 974 | push_space = BTRFS_LEAF_DATA_SIZE(root) - |
0783fcfc | 975 | btrfs_item_offset(right->items + push_items -1); |
123abc88 CM |
976 | memcpy(btrfs_leaf_data(left) + leaf_data_end(root, left) - push_space, |
977 | btrfs_leaf_data(right) + | |
978 | btrfs_item_offset(right->items + push_items - 1), | |
be0e5c09 | 979 | push_space); |
7518a238 | 980 | old_left_nritems = btrfs_header_nritems(&left->header); |
eb60ceac CM |
981 | BUG_ON(old_left_nritems < 0); |
982 | ||
0783fcfc | 983 | for (i = old_left_nritems; i < old_left_nritems + push_items; i++) { |
123abc88 CM |
984 | u32 ioff = btrfs_item_offset(left->items + i); |
985 | btrfs_set_item_offset(left->items + i, ioff - | |
986 | (BTRFS_LEAF_DATA_SIZE(root) - | |
0783fcfc CM |
987 | btrfs_item_offset(left->items + |
988 | old_left_nritems - 1))); | |
be0e5c09 | 989 | } |
7518a238 | 990 | btrfs_set_header_nritems(&left->header, old_left_nritems + push_items); |
be0e5c09 CM |
991 | |
992 | /* fixup right node */ | |
0783fcfc | 993 | push_space = btrfs_item_offset(right->items + push_items - 1) - |
123abc88 CM |
994 | leaf_data_end(root, right); |
995 | memmove(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - | |
996 | push_space, btrfs_leaf_data(right) + | |
997 | leaf_data_end(root, right), push_space); | |
be0e5c09 | 998 | memmove(right->items, right->items + push_items, |
7518a238 | 999 | (btrfs_header_nritems(&right->header) - push_items) * |
0783fcfc | 1000 | sizeof(struct btrfs_item)); |
7518a238 CM |
1001 | btrfs_set_header_nritems(&right->header, |
1002 | btrfs_header_nritems(&right->header) - | |
1003 | push_items); | |
123abc88 | 1004 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
eb60ceac | 1005 | |
7518a238 | 1006 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
0783fcfc CM |
1007 | btrfs_set_item_offset(right->items + i, push_space - |
1008 | btrfs_item_size(right->items + i)); | |
1009 | push_space = btrfs_item_offset(right->items + i); | |
be0e5c09 | 1010 | } |
eb60ceac | 1011 | |
d5719762 CM |
1012 | mark_buffer_dirty(t); |
1013 | mark_buffer_dirty(right_buf); | |
eb60ceac | 1014 | |
e089f05c | 1015 | wret = fixup_low_keys(trans, root, path, &right->items[0].key, 1); |
aa5d6bed CM |
1016 | if (wret) |
1017 | ret = wret; | |
be0e5c09 CM |
1018 | |
1019 | /* then fixup the leaf pointer in the path */ | |
1020 | if (path->slots[0] < push_items) { | |
1021 | path->slots[0] += old_left_nritems; | |
234b63a0 | 1022 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1023 | path->nodes[0] = t; |
be0e5c09 CM |
1024 | path->slots[1] -= 1; |
1025 | } else { | |
234b63a0 | 1026 | btrfs_block_release(root, t); |
be0e5c09 CM |
1027 | path->slots[0] -= push_items; |
1028 | } | |
eb60ceac | 1029 | BUG_ON(path->slots[0] < 0); |
aa5d6bed | 1030 | return ret; |
be0e5c09 CM |
1031 | } |
1032 | ||
74123bd7 CM |
1033 | /* |
1034 | * split the path's leaf in two, making sure there is at least data_size | |
1035 | * available for the resulting leaf level of the path. | |
aa5d6bed CM |
1036 | * |
1037 | * returns 0 if all went well and < 0 on failure. | |
74123bd7 | 1038 | */ |
e089f05c CM |
1039 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root |
1040 | *root, struct btrfs_path *path, int data_size) | |
be0e5c09 | 1041 | { |
e20d96d6 | 1042 | struct buffer_head *l_buf; |
234b63a0 | 1043 | struct btrfs_leaf *l; |
7518a238 | 1044 | u32 nritems; |
eb60ceac CM |
1045 | int mid; |
1046 | int slot; | |
234b63a0 | 1047 | struct btrfs_leaf *right; |
e20d96d6 | 1048 | struct buffer_head *right_buffer; |
0783fcfc | 1049 | int space_needed = data_size + sizeof(struct btrfs_item); |
be0e5c09 CM |
1050 | int data_copy_size; |
1051 | int rt_data_off; | |
1052 | int i; | |
1053 | int ret; | |
aa5d6bed CM |
1054 | int wret; |
1055 | ||
40689478 | 1056 | /* first try to make some room by pushing left and right */ |
e089f05c | 1057 | wret = push_leaf_left(trans, root, path, data_size); |
eaee50e8 CM |
1058 | if (wret < 0) |
1059 | return wret; | |
1060 | if (wret) { | |
e089f05c | 1061 | wret = push_leaf_right(trans, root, path, data_size); |
eaee50e8 CM |
1062 | if (wret < 0) |
1063 | return wret; | |
1064 | } | |
aa5d6bed | 1065 | l_buf = path->nodes[0]; |
e20d96d6 | 1066 | l = btrfs_buffer_leaf(l_buf); |
aa5d6bed CM |
1067 | |
1068 | /* did the pushes work? */ | |
123abc88 CM |
1069 | if (btrfs_leaf_free_space(root, l) >= |
1070 | sizeof(struct btrfs_item) + data_size) | |
aa5d6bed CM |
1071 | return 0; |
1072 | ||
5c680ed6 | 1073 | if (!path->nodes[1]) { |
e089f05c | 1074 | ret = insert_new_root(trans, root, path, 1); |
5c680ed6 CM |
1075 | if (ret) |
1076 | return ret; | |
1077 | } | |
eb60ceac | 1078 | slot = path->slots[0]; |
7518a238 | 1079 | nritems = btrfs_header_nritems(&l->header); |
eb60ceac | 1080 | mid = (nritems + 1)/ 2; |
e089f05c | 1081 | right_buffer = btrfs_alloc_free_block(trans, root); |
eb60ceac CM |
1082 | BUG_ON(!right_buffer); |
1083 | BUG_ON(mid == nritems); | |
e20d96d6 | 1084 | right = btrfs_buffer_leaf(right_buffer); |
123abc88 | 1085 | memset(&right->header, 0, sizeof(right->header)); |
be0e5c09 | 1086 | if (mid <= slot) { |
97571fd0 | 1087 | /* FIXME, just alloc a new leaf here */ |
be0e5c09 | 1088 | if (leaf_space_used(l, mid, nritems - mid) + space_needed > |
123abc88 | 1089 | BTRFS_LEAF_DATA_SIZE(root)) |
be0e5c09 CM |
1090 | BUG(); |
1091 | } else { | |
97571fd0 | 1092 | /* FIXME, just alloc a new leaf here */ |
be0e5c09 | 1093 | if (leaf_space_used(l, 0, mid + 1) + space_needed > |
123abc88 | 1094 | BTRFS_LEAF_DATA_SIZE(root)) |
be0e5c09 CM |
1095 | BUG(); |
1096 | } | |
7518a238 | 1097 | btrfs_set_header_nritems(&right->header, nritems - mid); |
e20d96d6 | 1098 | btrfs_set_header_blocknr(&right->header, right_buffer->b_blocknr); |
7518a238 CM |
1099 | btrfs_set_header_level(&right->header, 0); |
1100 | btrfs_set_header_parentid(&right->header, | |
e20d96d6 | 1101 | btrfs_header_parentid(btrfs_buffer_header(root->node))); |
123abc88 CM |
1102 | data_copy_size = btrfs_item_end(l->items + mid) - |
1103 | leaf_data_end(root, l); | |
be0e5c09 | 1104 | memcpy(right->items, l->items + mid, |
0783fcfc | 1105 | (nritems - mid) * sizeof(struct btrfs_item)); |
123abc88 CM |
1106 | memcpy(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - |
1107 | data_copy_size, btrfs_leaf_data(l) + | |
1108 | leaf_data_end(root, l), data_copy_size); | |
1109 | rt_data_off = BTRFS_LEAF_DATA_SIZE(root) - | |
1110 | btrfs_item_end(l->items + mid); | |
74123bd7 | 1111 | |
0783fcfc | 1112 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
123abc88 | 1113 | u32 ioff = btrfs_item_offset(right->items + i); |
0783fcfc CM |
1114 | btrfs_set_item_offset(right->items + i, ioff + rt_data_off); |
1115 | } | |
74123bd7 | 1116 | |
7518a238 | 1117 | btrfs_set_header_nritems(&l->header, mid); |
aa5d6bed | 1118 | ret = 0; |
e089f05c | 1119 | wret = insert_ptr(trans, root, path, &right->items[0].key, |
e20d96d6 | 1120 | right_buffer->b_blocknr, path->slots[1] + 1, 1); |
aa5d6bed CM |
1121 | if (wret) |
1122 | ret = wret; | |
d5719762 CM |
1123 | mark_buffer_dirty(right_buffer); |
1124 | mark_buffer_dirty(l_buf); | |
eb60ceac | 1125 | BUG_ON(path->slots[0] != slot); |
be0e5c09 | 1126 | if (mid <= slot) { |
234b63a0 | 1127 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1128 | path->nodes[0] = right_buffer; |
be0e5c09 CM |
1129 | path->slots[0] -= mid; |
1130 | path->slots[1] += 1; | |
eb60ceac | 1131 | } else |
234b63a0 | 1132 | btrfs_block_release(root, right_buffer); |
eb60ceac | 1133 | BUG_ON(path->slots[0] < 0); |
be0e5c09 CM |
1134 | return ret; |
1135 | } | |
1136 | ||
74123bd7 CM |
1137 | /* |
1138 | * Given a key and some data, insert an item into the tree. | |
1139 | * This does all the path init required, making room in the tree if needed. | |
1140 | */ | |
e089f05c CM |
1141 | int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1142 | *root, struct btrfs_path *path, struct btrfs_key | |
1143 | *cpu_key, u32 data_size) | |
be0e5c09 | 1144 | { |
aa5d6bed | 1145 | int ret = 0; |
be0e5c09 | 1146 | int slot; |
eb60ceac | 1147 | int slot_orig; |
234b63a0 | 1148 | struct btrfs_leaf *leaf; |
e20d96d6 | 1149 | struct buffer_head *leaf_buf; |
7518a238 | 1150 | u32 nritems; |
be0e5c09 | 1151 | unsigned int data_end; |
e2fa7227 CM |
1152 | struct btrfs_disk_key disk_key; |
1153 | ||
1154 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); | |
be0e5c09 | 1155 | |
74123bd7 | 1156 | /* create a root if there isn't one */ |
5c680ed6 | 1157 | if (!root->node) |
cfaa7295 | 1158 | BUG(); |
e089f05c | 1159 | ret = btrfs_search_slot(trans, root, cpu_key, path, data_size, 1); |
eb60ceac | 1160 | if (ret == 0) { |
62e2749e | 1161 | btrfs_release_path(root, path); |
f0930a37 | 1162 | return -EEXIST; |
aa5d6bed | 1163 | } |
ed2ff2cb CM |
1164 | if (ret < 0) |
1165 | goto out; | |
be0e5c09 | 1166 | |
62e2749e CM |
1167 | slot_orig = path->slots[0]; |
1168 | leaf_buf = path->nodes[0]; | |
e20d96d6 | 1169 | leaf = btrfs_buffer_leaf(leaf_buf); |
74123bd7 | 1170 | |
7518a238 | 1171 | nritems = btrfs_header_nritems(&leaf->header); |
123abc88 | 1172 | data_end = leaf_data_end(root, leaf); |
eb60ceac | 1173 | |
123abc88 | 1174 | if (btrfs_leaf_free_space(root, leaf) < |
234b63a0 | 1175 | sizeof(struct btrfs_item) + data_size) |
be0e5c09 CM |
1176 | BUG(); |
1177 | ||
62e2749e | 1178 | slot = path->slots[0]; |
eb60ceac | 1179 | BUG_ON(slot < 0); |
be0e5c09 CM |
1180 | if (slot != nritems) { |
1181 | int i; | |
0783fcfc | 1182 | unsigned int old_data = btrfs_item_end(leaf->items + slot); |
be0e5c09 CM |
1183 | |
1184 | /* | |
1185 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1186 | */ | |
1187 | /* first correct the data pointers */ | |
0783fcfc | 1188 | for (i = slot; i < nritems; i++) { |
123abc88 | 1189 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
1190 | btrfs_set_item_offset(leaf->items + i, |
1191 | ioff - data_size); | |
1192 | } | |
be0e5c09 CM |
1193 | |
1194 | /* shift the items */ | |
1195 | memmove(leaf->items + slot + 1, leaf->items + slot, | |
0783fcfc | 1196 | (nritems - slot) * sizeof(struct btrfs_item)); |
be0e5c09 CM |
1197 | |
1198 | /* shift the data */ | |
123abc88 CM |
1199 | memmove(btrfs_leaf_data(leaf) + data_end - data_size, |
1200 | btrfs_leaf_data(leaf) + | |
be0e5c09 CM |
1201 | data_end, old_data - data_end); |
1202 | data_end = old_data; | |
1203 | } | |
62e2749e | 1204 | /* setup the item for the new data */ |
e2fa7227 CM |
1205 | memcpy(&leaf->items[slot].key, &disk_key, |
1206 | sizeof(struct btrfs_disk_key)); | |
0783fcfc CM |
1207 | btrfs_set_item_offset(leaf->items + slot, data_end - data_size); |
1208 | btrfs_set_item_size(leaf->items + slot, data_size); | |
7518a238 | 1209 | btrfs_set_header_nritems(&leaf->header, nritems + 1); |
d5719762 | 1210 | mark_buffer_dirty(leaf_buf); |
aa5d6bed CM |
1211 | |
1212 | ret = 0; | |
8e19f2cd | 1213 | if (slot == 0) |
e089f05c | 1214 | ret = fixup_low_keys(trans, root, path, &disk_key, 1); |
aa5d6bed | 1215 | |
123abc88 | 1216 | if (btrfs_leaf_free_space(root, leaf) < 0) |
be0e5c09 | 1217 | BUG(); |
62e2749e | 1218 | check_leaf(root, path, 0); |
ed2ff2cb | 1219 | out: |
62e2749e CM |
1220 | return ret; |
1221 | } | |
1222 | ||
1223 | /* | |
1224 | * Given a key and some data, insert an item into the tree. | |
1225 | * This does all the path init required, making room in the tree if needed. | |
1226 | */ | |
e089f05c CM |
1227 | int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1228 | *root, struct btrfs_key *cpu_key, void *data, u32 | |
1229 | data_size) | |
62e2749e CM |
1230 | { |
1231 | int ret = 0; | |
1232 | struct btrfs_path path; | |
1233 | u8 *ptr; | |
1234 | ||
1235 | btrfs_init_path(&path); | |
e089f05c | 1236 | ret = btrfs_insert_empty_item(trans, root, &path, cpu_key, data_size); |
62e2749e | 1237 | if (!ret) { |
e20d96d6 CM |
1238 | ptr = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), |
1239 | path.slots[0], u8); | |
62e2749e | 1240 | memcpy(ptr, data, data_size); |
d5719762 | 1241 | mark_buffer_dirty(path.nodes[0]); |
62e2749e | 1242 | } |
234b63a0 | 1243 | btrfs_release_path(root, &path); |
aa5d6bed | 1244 | return ret; |
be0e5c09 CM |
1245 | } |
1246 | ||
74123bd7 | 1247 | /* |
5de08d7d | 1248 | * delete the pointer from a given node. |
74123bd7 CM |
1249 | * |
1250 | * If the delete empties a node, the node is removed from the tree, | |
1251 | * continuing all the way the root if required. The root is converted into | |
1252 | * a leaf if all the nodes are emptied. | |
1253 | */ | |
e089f05c CM |
1254 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
1255 | struct btrfs_path *path, int level, int slot) | |
be0e5c09 | 1256 | { |
234b63a0 | 1257 | struct btrfs_node *node; |
e20d96d6 | 1258 | struct buffer_head *parent = path->nodes[level]; |
7518a238 | 1259 | u32 nritems; |
aa5d6bed | 1260 | int ret = 0; |
bb803951 | 1261 | int wret; |
be0e5c09 | 1262 | |
e20d96d6 | 1263 | node = btrfs_buffer_node(parent); |
7518a238 | 1264 | nritems = btrfs_header_nritems(&node->header); |
bb803951 | 1265 | if (slot != nritems -1) { |
123abc88 CM |
1266 | memmove(node->ptrs + slot, node->ptrs + slot + 1, |
1267 | sizeof(struct btrfs_key_ptr) * (nritems - slot - 1)); | |
bb803951 | 1268 | } |
7518a238 CM |
1269 | nritems--; |
1270 | btrfs_set_header_nritems(&node->header, nritems); | |
1271 | if (nritems == 0 && parent == root->node) { | |
e20d96d6 CM |
1272 | struct btrfs_header *header = btrfs_buffer_header(root->node); |
1273 | BUG_ON(btrfs_header_level(header) != 1); | |
bb803951 | 1274 | /* just turn the root into a leaf and break */ |
e20d96d6 | 1275 | btrfs_set_header_level(header, 0); |
bb803951 | 1276 | } else if (slot == 0) { |
e089f05c | 1277 | wret = fixup_low_keys(trans, root, path, &node->ptrs[0].key, |
123abc88 | 1278 | level + 1); |
0f70abe2 CM |
1279 | if (wret) |
1280 | ret = wret; | |
be0e5c09 | 1281 | } |
d5719762 | 1282 | mark_buffer_dirty(parent); |
aa5d6bed | 1283 | return ret; |
be0e5c09 CM |
1284 | } |
1285 | ||
74123bd7 CM |
1286 | /* |
1287 | * delete the item at the leaf level in path. If that empties | |
1288 | * the leaf, remove it from the tree | |
1289 | */ | |
e089f05c CM |
1290 | int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
1291 | struct btrfs_path *path) | |
be0e5c09 | 1292 | { |
be0e5c09 | 1293 | int slot; |
234b63a0 | 1294 | struct btrfs_leaf *leaf; |
e20d96d6 | 1295 | struct buffer_head *leaf_buf; |
be0e5c09 CM |
1296 | int doff; |
1297 | int dsize; | |
aa5d6bed CM |
1298 | int ret = 0; |
1299 | int wret; | |
7518a238 | 1300 | u32 nritems; |
be0e5c09 | 1301 | |
eb60ceac | 1302 | leaf_buf = path->nodes[0]; |
e20d96d6 | 1303 | leaf = btrfs_buffer_leaf(leaf_buf); |
4920c9ac | 1304 | slot = path->slots[0]; |
0783fcfc CM |
1305 | doff = btrfs_item_offset(leaf->items + slot); |
1306 | dsize = btrfs_item_size(leaf->items + slot); | |
7518a238 | 1307 | nritems = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 1308 | |
7518a238 | 1309 | if (slot != nritems - 1) { |
be0e5c09 | 1310 | int i; |
123abc88 CM |
1311 | int data_end = leaf_data_end(root, leaf); |
1312 | memmove(btrfs_leaf_data(leaf) + data_end + dsize, | |
1313 | btrfs_leaf_data(leaf) + data_end, | |
be0e5c09 | 1314 | doff - data_end); |
0783fcfc | 1315 | for (i = slot + 1; i < nritems; i++) { |
123abc88 | 1316 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
1317 | btrfs_set_item_offset(leaf->items + i, ioff + dsize); |
1318 | } | |
be0e5c09 | 1319 | memmove(leaf->items + slot, leaf->items + slot + 1, |
0783fcfc | 1320 | sizeof(struct btrfs_item) * |
7518a238 | 1321 | (nritems - slot - 1)); |
be0e5c09 | 1322 | } |
7518a238 CM |
1323 | btrfs_set_header_nritems(&leaf->header, nritems - 1); |
1324 | nritems--; | |
74123bd7 | 1325 | /* delete the leaf if we've emptied it */ |
7518a238 | 1326 | if (nritems == 0) { |
eb60ceac | 1327 | if (leaf_buf == root->node) { |
7518a238 | 1328 | btrfs_set_header_level(&leaf->header, 0); |
9a8dd150 | 1329 | } else { |
e089f05c CM |
1330 | clean_tree_block(trans, root, leaf_buf); |
1331 | wret = del_ptr(trans, root, path, 1, path->slots[1]); | |
aa5d6bed CM |
1332 | if (wret) |
1333 | ret = wret; | |
e089f05c | 1334 | wret = btrfs_free_extent(trans, root, |
e20d96d6 | 1335 | leaf_buf->b_blocknr, 1, 1); |
0f70abe2 CM |
1336 | if (wret) |
1337 | ret = wret; | |
9a8dd150 | 1338 | } |
be0e5c09 | 1339 | } else { |
7518a238 | 1340 | int used = leaf_space_used(leaf, 0, nritems); |
aa5d6bed | 1341 | if (slot == 0) { |
e089f05c CM |
1342 | wret = fixup_low_keys(trans, root, path, |
1343 | &leaf->items[0].key, 1); | |
aa5d6bed CM |
1344 | if (wret) |
1345 | ret = wret; | |
1346 | } | |
aa5d6bed | 1347 | |
74123bd7 | 1348 | /* delete the leaf if it is mostly empty */ |
123abc88 | 1349 | if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) { |
be0e5c09 CM |
1350 | /* push_leaf_left fixes the path. |
1351 | * make sure the path still points to our leaf | |
1352 | * for possible call to del_ptr below | |
1353 | */ | |
4920c9ac | 1354 | slot = path->slots[1]; |
e20d96d6 | 1355 | get_bh(leaf_buf); |
e089f05c | 1356 | wret = push_leaf_left(trans, root, path, 1); |
aa5d6bed CM |
1357 | if (wret < 0) |
1358 | ret = wret; | |
f0930a37 | 1359 | if (path->nodes[0] == leaf_buf && |
7518a238 | 1360 | btrfs_header_nritems(&leaf->header)) { |
e089f05c | 1361 | wret = push_leaf_right(trans, root, path, 1); |
aa5d6bed CM |
1362 | if (wret < 0) |
1363 | ret = wret; | |
1364 | } | |
7518a238 | 1365 | if (btrfs_header_nritems(&leaf->header) == 0) { |
e20d96d6 | 1366 | u64 blocknr = leaf_buf->b_blocknr; |
e089f05c CM |
1367 | clean_tree_block(trans, root, leaf_buf); |
1368 | wret = del_ptr(trans, root, path, 1, slot); | |
aa5d6bed CM |
1369 | if (wret) |
1370 | ret = wret; | |
234b63a0 | 1371 | btrfs_block_release(root, leaf_buf); |
e089f05c CM |
1372 | wret = btrfs_free_extent(trans, root, blocknr, |
1373 | 1, 1); | |
0f70abe2 CM |
1374 | if (wret) |
1375 | ret = wret; | |
5de08d7d | 1376 | } else { |
d5719762 | 1377 | mark_buffer_dirty(leaf_buf); |
234b63a0 | 1378 | btrfs_block_release(root, leaf_buf); |
be0e5c09 | 1379 | } |
d5719762 CM |
1380 | } else { |
1381 | mark_buffer_dirty(leaf_buf); | |
be0e5c09 CM |
1382 | } |
1383 | } | |
aa5d6bed | 1384 | return ret; |
be0e5c09 CM |
1385 | } |
1386 | ||
97571fd0 CM |
1387 | /* |
1388 | * walk up the tree as far as required to find the next leaf. | |
0f70abe2 CM |
1389 | * returns 0 if it found something or 1 if there are no greater leaves. |
1390 | * returns < 0 on io errors. | |
97571fd0 | 1391 | */ |
234b63a0 | 1392 | int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) |
d97e63b6 CM |
1393 | { |
1394 | int slot; | |
1395 | int level = 1; | |
1396 | u64 blocknr; | |
e20d96d6 CM |
1397 | struct buffer_head *c; |
1398 | struct btrfs_node *c_node; | |
1399 | struct buffer_head *next = NULL; | |
d97e63b6 | 1400 | |
234b63a0 | 1401 | while(level < BTRFS_MAX_LEVEL) { |
d97e63b6 | 1402 | if (!path->nodes[level]) |
0f70abe2 | 1403 | return 1; |
d97e63b6 CM |
1404 | slot = path->slots[level] + 1; |
1405 | c = path->nodes[level]; | |
e20d96d6 CM |
1406 | c_node = btrfs_buffer_node(c); |
1407 | if (slot >= btrfs_header_nritems(&c_node->header)) { | |
d97e63b6 CM |
1408 | level++; |
1409 | continue; | |
1410 | } | |
e20d96d6 | 1411 | blocknr = btrfs_node_blockptr(c_node, slot); |
cfaa7295 | 1412 | if (next) |
234b63a0 | 1413 | btrfs_block_release(root, next); |
d97e63b6 CM |
1414 | next = read_tree_block(root, blocknr); |
1415 | break; | |
1416 | } | |
1417 | path->slots[level] = slot; | |
1418 | while(1) { | |
1419 | level--; | |
1420 | c = path->nodes[level]; | |
234b63a0 | 1421 | btrfs_block_release(root, c); |
d97e63b6 CM |
1422 | path->nodes[level] = next; |
1423 | path->slots[level] = 0; | |
1424 | if (!level) | |
1425 | break; | |
1d4f8a0c | 1426 | next = read_tree_block(root, |
e20d96d6 | 1427 | btrfs_node_blockptr(btrfs_buffer_node(next), 0)); |
d97e63b6 CM |
1428 | } |
1429 | return 0; | |
1430 | } |