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Commit | Line | Data |
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2e635a27 | 1 | #include <linux/module.h> |
eb60ceac CM |
2 | #include "ctree.h" |
3 | #include "disk-io.h" | |
7f5c1516 | 4 | #include "transaction.h" |
9a8dd150 | 5 | |
e089f05c CM |
6 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
7 | *root, struct btrfs_path *path, int level); | |
8 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root | |
d4dbff95 CM |
9 | *root, struct btrfs_key *ins_key, |
10 | struct btrfs_path *path, int data_size); | |
e089f05c | 11 | static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root |
e20d96d6 | 12 | *root, struct buffer_head *dst, struct buffer_head |
e089f05c CM |
13 | *src); |
14 | static int balance_node_right(struct btrfs_trans_handle *trans, struct | |
e20d96d6 CM |
15 | btrfs_root *root, struct buffer_head *dst_buf, |
16 | struct buffer_head *src_buf); | |
e089f05c CM |
17 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
18 | struct btrfs_path *path, int level, int slot); | |
d97e63b6 | 19 | |
df24a2b9 | 20 | inline void btrfs_init_path(struct btrfs_path *p) |
2c90e5d6 | 21 | { |
df24a2b9 | 22 | memset(p, 0, sizeof(*p)); |
2c90e5d6 CM |
23 | } |
24 | ||
df24a2b9 | 25 | struct btrfs_path *btrfs_alloc_path(void) |
2c90e5d6 | 26 | { |
df24a2b9 CM |
27 | struct btrfs_path *path; |
28 | path = kmem_cache_alloc(btrfs_path_cachep, GFP_NOFS); | |
29 | if (path) | |
30 | btrfs_init_path(path); | |
31 | return path; | |
2c90e5d6 CM |
32 | } |
33 | ||
df24a2b9 | 34 | void btrfs_free_path(struct btrfs_path *p) |
be0e5c09 | 35 | { |
df24a2b9 CM |
36 | btrfs_release_path(NULL, p); |
37 | kmem_cache_free(btrfs_path_cachep, p); | |
be0e5c09 CM |
38 | } |
39 | ||
234b63a0 | 40 | void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p) |
eb60ceac CM |
41 | { |
42 | int i; | |
234b63a0 | 43 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
eb60ceac CM |
44 | if (!p->nodes[i]) |
45 | break; | |
234b63a0 | 46 | btrfs_block_release(root, p->nodes[i]); |
eb60ceac | 47 | } |
aa5d6bed | 48 | memset(p, 0, sizeof(*p)); |
eb60ceac CM |
49 | } |
50 | ||
e089f05c | 51 | static int btrfs_cow_block(struct btrfs_trans_handle *trans, struct btrfs_root |
e20d96d6 CM |
52 | *root, struct buffer_head *buf, struct buffer_head |
53 | *parent, int parent_slot, struct buffer_head | |
e089f05c | 54 | **cow_ret) |
02217ed2 | 55 | { |
e20d96d6 CM |
56 | struct buffer_head *cow; |
57 | struct btrfs_node *cow_node; | |
02217ed2 | 58 | |
7f5c1516 CM |
59 | if (btrfs_header_generation(btrfs_buffer_header(buf)) == |
60 | trans->transid) { | |
02217ed2 CM |
61 | *cow_ret = buf; |
62 | return 0; | |
63 | } | |
e089f05c | 64 | cow = btrfs_alloc_free_block(trans, root); |
e20d96d6 | 65 | cow_node = btrfs_buffer_node(cow); |
2c90e5d6 CM |
66 | if (buf->b_size != root->blocksize || cow->b_size != root->blocksize) |
67 | WARN_ON(1); | |
e20d96d6 | 68 | memcpy(cow_node, btrfs_buffer_node(buf), root->blocksize); |
7eccb903 | 69 | btrfs_set_header_blocknr(&cow_node->header, bh_blocknr(cow)); |
7f5c1516 | 70 | btrfs_set_header_generation(&cow_node->header, trans->transid); |
e089f05c | 71 | btrfs_inc_ref(trans, root, buf); |
02217ed2 CM |
72 | if (buf == root->node) { |
73 | root->node = cow; | |
e20d96d6 | 74 | get_bh(cow); |
2c90e5d6 | 75 | if (buf != root->commit_root) { |
7eccb903 | 76 | btrfs_free_extent(trans, root, bh_blocknr(buf), 1, 1); |
2c90e5d6 | 77 | } |
234b63a0 | 78 | btrfs_block_release(root, buf); |
02217ed2 | 79 | } else { |
e20d96d6 | 80 | btrfs_set_node_blockptr(btrfs_buffer_node(parent), parent_slot, |
7eccb903 | 81 | bh_blocknr(cow)); |
d6025579 | 82 | btrfs_mark_buffer_dirty(parent); |
7eccb903 | 83 | btrfs_free_extent(trans, root, bh_blocknr(buf), 1, 1); |
02217ed2 | 84 | } |
234b63a0 | 85 | btrfs_block_release(root, buf); |
df24a2b9 | 86 | mark_buffer_dirty(cow); |
2c90e5d6 | 87 | *cow_ret = cow; |
02217ed2 CM |
88 | return 0; |
89 | } | |
90 | ||
74123bd7 CM |
91 | /* |
92 | * The leaf data grows from end-to-front in the node. | |
93 | * this returns the address of the start of the last item, | |
94 | * which is the stop of the leaf data stack | |
95 | */ | |
123abc88 CM |
96 | static inline unsigned int leaf_data_end(struct btrfs_root *root, |
97 | struct btrfs_leaf *leaf) | |
be0e5c09 | 98 | { |
7518a238 | 99 | u32 nr = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 100 | if (nr == 0) |
123abc88 | 101 | return BTRFS_LEAF_DATA_SIZE(root); |
0783fcfc | 102 | return btrfs_item_offset(leaf->items + nr - 1); |
be0e5c09 CM |
103 | } |
104 | ||
74123bd7 CM |
105 | /* |
106 | * compare two keys in a memcmp fashion | |
107 | */ | |
9aca1d51 | 108 | static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2) |
be0e5c09 | 109 | { |
e2fa7227 CM |
110 | struct btrfs_key k1; |
111 | ||
112 | btrfs_disk_key_to_cpu(&k1, disk); | |
113 | ||
114 | if (k1.objectid > k2->objectid) | |
be0e5c09 | 115 | return 1; |
e2fa7227 | 116 | if (k1.objectid < k2->objectid) |
be0e5c09 | 117 | return -1; |
f254e52c CM |
118 | if (k1.flags > k2->flags) |
119 | return 1; | |
120 | if (k1.flags < k2->flags) | |
121 | return -1; | |
70b2befd CM |
122 | if (k1.offset > k2->offset) |
123 | return 1; | |
124 | if (k1.offset < k2->offset) | |
125 | return -1; | |
be0e5c09 CM |
126 | return 0; |
127 | } | |
74123bd7 | 128 | |
123abc88 CM |
129 | static int check_node(struct btrfs_root *root, struct btrfs_path *path, |
130 | int level) | |
aa5d6bed CM |
131 | { |
132 | int i; | |
234b63a0 | 133 | struct btrfs_node *parent = NULL; |
e20d96d6 | 134 | struct btrfs_node *node = btrfs_buffer_node(path->nodes[level]); |
aa5d6bed | 135 | int parent_slot; |
7518a238 | 136 | u32 nritems = btrfs_header_nritems(&node->header); |
aa5d6bed CM |
137 | |
138 | if (path->nodes[level + 1]) | |
e20d96d6 | 139 | parent = btrfs_buffer_node(path->nodes[level + 1]); |
aa5d6bed | 140 | parent_slot = path->slots[level + 1]; |
7518a238 CM |
141 | BUG_ON(nritems == 0); |
142 | if (parent) { | |
e2fa7227 | 143 | struct btrfs_disk_key *parent_key; |
123abc88 CM |
144 | parent_key = &parent->ptrs[parent_slot].key; |
145 | BUG_ON(memcmp(parent_key, &node->ptrs[0].key, | |
e2fa7227 | 146 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 147 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
7518a238 | 148 | btrfs_header_blocknr(&node->header)); |
aa5d6bed | 149 | } |
123abc88 | 150 | BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root)); |
7518a238 | 151 | for (i = 0; nritems > 1 && i < nritems - 2; i++) { |
e2fa7227 | 152 | struct btrfs_key cpukey; |
123abc88 | 153 | btrfs_disk_key_to_cpu(&cpukey, &node->ptrs[i + 1].key); |
e66f709b CM |
154 | if (comp_keys(&node->ptrs[i].key, &cpukey) >= 0) { |
155 | struct btrfs_key bad; | |
156 | btrfs_disk_key_to_cpu(&bad, &node->ptrs[i].key); | |
157 | printk("check_node level %d i is %d bad comp %Lu %u %Lu, %Lu %u %Lu\n",level, i, bad.objectid, bad.flags, bad.offset, cpukey.objectid, cpukey.flags, cpukey.offset); | |
158 | } | |
123abc88 | 159 | BUG_ON(comp_keys(&node->ptrs[i].key, &cpukey) >= 0); |
aa5d6bed CM |
160 | } |
161 | return 0; | |
162 | } | |
163 | ||
123abc88 CM |
164 | static int check_leaf(struct btrfs_root *root, struct btrfs_path *path, |
165 | int level) | |
aa5d6bed CM |
166 | { |
167 | int i; | |
e20d96d6 | 168 | struct btrfs_leaf *leaf = btrfs_buffer_leaf(path->nodes[level]); |
234b63a0 | 169 | struct btrfs_node *parent = NULL; |
aa5d6bed | 170 | int parent_slot; |
7518a238 | 171 | u32 nritems = btrfs_header_nritems(&leaf->header); |
aa5d6bed CM |
172 | |
173 | if (path->nodes[level + 1]) | |
e20d96d6 | 174 | parent = btrfs_buffer_node(path->nodes[level + 1]); |
aa5d6bed | 175 | parent_slot = path->slots[level + 1]; |
123abc88 | 176 | BUG_ON(btrfs_leaf_free_space(root, leaf) < 0); |
7518a238 CM |
177 | |
178 | if (nritems == 0) | |
179 | return 0; | |
180 | ||
181 | if (parent) { | |
e2fa7227 | 182 | struct btrfs_disk_key *parent_key; |
123abc88 | 183 | parent_key = &parent->ptrs[parent_slot].key; |
aa5d6bed | 184 | BUG_ON(memcmp(parent_key, &leaf->items[0].key, |
e2fa7227 | 185 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 186 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
7518a238 | 187 | btrfs_header_blocknr(&leaf->header)); |
aa5d6bed | 188 | } |
7518a238 | 189 | for (i = 0; nritems > 1 && i < nritems - 2; i++) { |
e2fa7227 CM |
190 | struct btrfs_key cpukey; |
191 | btrfs_disk_key_to_cpu(&cpukey, &leaf->items[i + 1].key); | |
aa5d6bed | 192 | BUG_ON(comp_keys(&leaf->items[i].key, |
e2fa7227 | 193 | &cpukey) >= 0); |
0783fcfc CM |
194 | BUG_ON(btrfs_item_offset(leaf->items + i) != |
195 | btrfs_item_end(leaf->items + i + 1)); | |
aa5d6bed | 196 | if (i == 0) { |
0783fcfc CM |
197 | BUG_ON(btrfs_item_offset(leaf->items + i) + |
198 | btrfs_item_size(leaf->items + i) != | |
123abc88 | 199 | BTRFS_LEAF_DATA_SIZE(root)); |
aa5d6bed CM |
200 | } |
201 | } | |
aa5d6bed CM |
202 | return 0; |
203 | } | |
204 | ||
123abc88 CM |
205 | static int check_block(struct btrfs_root *root, struct btrfs_path *path, |
206 | int level) | |
aa5d6bed | 207 | { |
3eb0314d CM |
208 | struct btrfs_node *node = btrfs_buffer_node(path->nodes[level]); |
209 | if (memcmp(node->header.fsid, root->fs_info->disk_super->fsid, | |
210 | sizeof(node->header.fsid))) | |
211 | BUG(); | |
aa5d6bed | 212 | if (level == 0) |
123abc88 CM |
213 | return check_leaf(root, path, level); |
214 | return check_node(root, path, level); | |
aa5d6bed CM |
215 | } |
216 | ||
74123bd7 CM |
217 | /* |
218 | * search for key in the array p. items p are item_size apart | |
219 | * and there are 'max' items in p | |
220 | * the slot in the array is returned via slot, and it points to | |
221 | * the place where you would insert key if it is not found in | |
222 | * the array. | |
223 | * | |
224 | * slot may point to max if the key is bigger than all of the keys | |
225 | */ | |
9aca1d51 | 226 | static int generic_bin_search(char *p, int item_size, struct btrfs_key *key, |
be0e5c09 CM |
227 | int max, int *slot) |
228 | { | |
229 | int low = 0; | |
230 | int high = max; | |
231 | int mid; | |
232 | int ret; | |
e2fa7227 | 233 | struct btrfs_disk_key *tmp; |
be0e5c09 CM |
234 | |
235 | while(low < high) { | |
236 | mid = (low + high) / 2; | |
e2fa7227 | 237 | tmp = (struct btrfs_disk_key *)(p + mid * item_size); |
be0e5c09 CM |
238 | ret = comp_keys(tmp, key); |
239 | ||
240 | if (ret < 0) | |
241 | low = mid + 1; | |
242 | else if (ret > 0) | |
243 | high = mid; | |
244 | else { | |
245 | *slot = mid; | |
246 | return 0; | |
247 | } | |
248 | } | |
249 | *slot = low; | |
250 | return 1; | |
251 | } | |
252 | ||
97571fd0 CM |
253 | /* |
254 | * simple bin_search frontend that does the right thing for | |
255 | * leaves vs nodes | |
256 | */ | |
9aca1d51 | 257 | static int bin_search(struct btrfs_node *c, struct btrfs_key *key, int *slot) |
be0e5c09 | 258 | { |
7518a238 | 259 | if (btrfs_is_leaf(c)) { |
234b63a0 | 260 | struct btrfs_leaf *l = (struct btrfs_leaf *)c; |
0783fcfc CM |
261 | return generic_bin_search((void *)l->items, |
262 | sizeof(struct btrfs_item), | |
7518a238 CM |
263 | key, btrfs_header_nritems(&c->header), |
264 | slot); | |
be0e5c09 | 265 | } else { |
123abc88 CM |
266 | return generic_bin_search((void *)c->ptrs, |
267 | sizeof(struct btrfs_key_ptr), | |
7518a238 CM |
268 | key, btrfs_header_nritems(&c->header), |
269 | slot); | |
be0e5c09 CM |
270 | } |
271 | return -1; | |
272 | } | |
273 | ||
e20d96d6 CM |
274 | static struct buffer_head *read_node_slot(struct btrfs_root *root, |
275 | struct buffer_head *parent_buf, | |
bb803951 CM |
276 | int slot) |
277 | { | |
e20d96d6 | 278 | struct btrfs_node *node = btrfs_buffer_node(parent_buf); |
bb803951 CM |
279 | if (slot < 0) |
280 | return NULL; | |
7518a238 | 281 | if (slot >= btrfs_header_nritems(&node->header)) |
bb803951 | 282 | return NULL; |
1d4f8a0c | 283 | return read_tree_block(root, btrfs_node_blockptr(node, slot)); |
bb803951 CM |
284 | } |
285 | ||
e089f05c CM |
286 | static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root |
287 | *root, struct btrfs_path *path, int level) | |
bb803951 | 288 | { |
e20d96d6 CM |
289 | struct buffer_head *right_buf; |
290 | struct buffer_head *mid_buf; | |
291 | struct buffer_head *left_buf; | |
292 | struct buffer_head *parent_buf = NULL; | |
234b63a0 CM |
293 | struct btrfs_node *right = NULL; |
294 | struct btrfs_node *mid; | |
295 | struct btrfs_node *left = NULL; | |
296 | struct btrfs_node *parent = NULL; | |
bb803951 CM |
297 | int ret = 0; |
298 | int wret; | |
299 | int pslot; | |
bb803951 | 300 | int orig_slot = path->slots[level]; |
79f95c82 | 301 | u64 orig_ptr; |
bb803951 CM |
302 | |
303 | if (level == 0) | |
304 | return 0; | |
305 | ||
306 | mid_buf = path->nodes[level]; | |
e20d96d6 | 307 | mid = btrfs_buffer_node(mid_buf); |
1d4f8a0c | 308 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
79f95c82 | 309 | |
234b63a0 | 310 | if (level < BTRFS_MAX_LEVEL - 1) |
bb803951 CM |
311 | parent_buf = path->nodes[level + 1]; |
312 | pslot = path->slots[level + 1]; | |
313 | ||
40689478 CM |
314 | /* |
315 | * deal with the case where there is only one pointer in the root | |
316 | * by promoting the node below to a root | |
317 | */ | |
bb803951 | 318 | if (!parent_buf) { |
e20d96d6 | 319 | struct buffer_head *child; |
7eccb903 | 320 | u64 blocknr = bh_blocknr(mid_buf); |
bb803951 | 321 | |
7518a238 | 322 | if (btrfs_header_nritems(&mid->header) != 1) |
bb803951 CM |
323 | return 0; |
324 | ||
325 | /* promote the child to a root */ | |
326 | child = read_node_slot(root, mid_buf, 0); | |
327 | BUG_ON(!child); | |
328 | root->node = child; | |
329 | path->nodes[level] = NULL; | |
d6025579 CM |
330 | clean_tree_block(trans, root, mid_buf); |
331 | wait_on_buffer(mid_buf); | |
bb803951 | 332 | /* once for the path */ |
234b63a0 | 333 | btrfs_block_release(root, mid_buf); |
bb803951 | 334 | /* once for the root ptr */ |
234b63a0 | 335 | btrfs_block_release(root, mid_buf); |
e089f05c | 336 | return btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 | 337 | } |
e20d96d6 | 338 | parent = btrfs_buffer_node(parent_buf); |
bb803951 | 339 | |
123abc88 CM |
340 | if (btrfs_header_nritems(&mid->header) > |
341 | BTRFS_NODEPTRS_PER_BLOCK(root) / 4) | |
bb803951 CM |
342 | return 0; |
343 | ||
bb803951 CM |
344 | left_buf = read_node_slot(root, parent_buf, pslot - 1); |
345 | right_buf = read_node_slot(root, parent_buf, pslot + 1); | |
79f95c82 CM |
346 | |
347 | /* first, try to make some room in the middle buffer */ | |
bb803951 | 348 | if (left_buf) { |
e089f05c CM |
349 | btrfs_cow_block(trans, root, left_buf, parent_buf, pslot - 1, |
350 | &left_buf); | |
e20d96d6 | 351 | left = btrfs_buffer_node(left_buf); |
7518a238 | 352 | orig_slot += btrfs_header_nritems(&left->header); |
e089f05c | 353 | wret = push_node_left(trans, root, left_buf, mid_buf); |
79f95c82 CM |
354 | if (wret < 0) |
355 | ret = wret; | |
bb803951 | 356 | } |
79f95c82 CM |
357 | |
358 | /* | |
359 | * then try to empty the right most buffer into the middle | |
360 | */ | |
bb803951 | 361 | if (right_buf) { |
e089f05c CM |
362 | btrfs_cow_block(trans, root, right_buf, parent_buf, pslot + 1, |
363 | &right_buf); | |
e20d96d6 | 364 | right = btrfs_buffer_node(right_buf); |
e089f05c | 365 | wret = push_node_left(trans, root, mid_buf, right_buf); |
79f95c82 CM |
366 | if (wret < 0) |
367 | ret = wret; | |
7518a238 | 368 | if (btrfs_header_nritems(&right->header) == 0) { |
7eccb903 | 369 | u64 blocknr = bh_blocknr(right_buf); |
e089f05c | 370 | clean_tree_block(trans, root, right_buf); |
d6025579 CM |
371 | wait_on_buffer(right_buf); |
372 | btrfs_block_release(root, right_buf); | |
bb803951 CM |
373 | right_buf = NULL; |
374 | right = NULL; | |
e089f05c CM |
375 | wret = del_ptr(trans, root, path, level + 1, pslot + |
376 | 1); | |
bb803951 CM |
377 | if (wret) |
378 | ret = wret; | |
e089f05c | 379 | wret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 CM |
380 | if (wret) |
381 | ret = wret; | |
382 | } else { | |
d6025579 CM |
383 | btrfs_memcpy(root, parent, |
384 | &parent->ptrs[pslot + 1].key, | |
385 | &right->ptrs[0].key, | |
386 | sizeof(struct btrfs_disk_key)); | |
387 | btrfs_mark_buffer_dirty(parent_buf); | |
bb803951 CM |
388 | } |
389 | } | |
7518a238 | 390 | if (btrfs_header_nritems(&mid->header) == 1) { |
79f95c82 CM |
391 | /* |
392 | * we're not allowed to leave a node with one item in the | |
393 | * tree during a delete. A deletion from lower in the tree | |
394 | * could try to delete the only pointer in this node. | |
395 | * So, pull some keys from the left. | |
396 | * There has to be a left pointer at this point because | |
397 | * otherwise we would have pulled some pointers from the | |
398 | * right | |
399 | */ | |
400 | BUG_ON(!left_buf); | |
e089f05c | 401 | wret = balance_node_right(trans, root, mid_buf, left_buf); |
79f95c82 CM |
402 | if (wret < 0) |
403 | ret = wret; | |
404 | BUG_ON(wret == 1); | |
405 | } | |
7518a238 | 406 | if (btrfs_header_nritems(&mid->header) == 0) { |
79f95c82 | 407 | /* we've managed to empty the middle node, drop it */ |
7eccb903 | 408 | u64 blocknr = bh_blocknr(mid_buf); |
e089f05c | 409 | clean_tree_block(trans, root, mid_buf); |
d6025579 CM |
410 | wait_on_buffer(mid_buf); |
411 | btrfs_block_release(root, mid_buf); | |
bb803951 CM |
412 | mid_buf = NULL; |
413 | mid = NULL; | |
e089f05c | 414 | wret = del_ptr(trans, root, path, level + 1, pslot); |
bb803951 CM |
415 | if (wret) |
416 | ret = wret; | |
e089f05c | 417 | wret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 CM |
418 | if (wret) |
419 | ret = wret; | |
79f95c82 CM |
420 | } else { |
421 | /* update the parent key to reflect our changes */ | |
d6025579 CM |
422 | btrfs_memcpy(root, parent, |
423 | &parent->ptrs[pslot].key, &mid->ptrs[0].key, | |
424 | sizeof(struct btrfs_disk_key)); | |
425 | btrfs_mark_buffer_dirty(parent_buf); | |
79f95c82 | 426 | } |
bb803951 | 427 | |
79f95c82 | 428 | /* update the path */ |
bb803951 | 429 | if (left_buf) { |
7518a238 | 430 | if (btrfs_header_nritems(&left->header) > orig_slot) { |
e20d96d6 | 431 | get_bh(left_buf); |
bb803951 CM |
432 | path->nodes[level] = left_buf; |
433 | path->slots[level + 1] -= 1; | |
434 | path->slots[level] = orig_slot; | |
435 | if (mid_buf) | |
234b63a0 | 436 | btrfs_block_release(root, mid_buf); |
bb803951 | 437 | } else { |
7518a238 | 438 | orig_slot -= btrfs_header_nritems(&left->header); |
bb803951 CM |
439 | path->slots[level] = orig_slot; |
440 | } | |
441 | } | |
79f95c82 | 442 | /* double check we haven't messed things up */ |
123abc88 | 443 | check_block(root, path, level); |
e20d96d6 CM |
444 | if (orig_ptr != |
445 | btrfs_node_blockptr(btrfs_buffer_node(path->nodes[level]), | |
446 | path->slots[level])) | |
79f95c82 | 447 | BUG(); |
bb803951 CM |
448 | |
449 | if (right_buf) | |
234b63a0 | 450 | btrfs_block_release(root, right_buf); |
bb803951 | 451 | if (left_buf) |
234b63a0 | 452 | btrfs_block_release(root, left_buf); |
bb803951 CM |
453 | return ret; |
454 | } | |
455 | ||
e66f709b CM |
456 | /* returns zero if the push worked, non-zero otherwise */ |
457 | static int push_nodes_for_insert(struct btrfs_trans_handle *trans, | |
458 | struct btrfs_root *root, | |
459 | struct btrfs_path *path, int level) | |
460 | { | |
461 | struct buffer_head *right_buf; | |
462 | struct buffer_head *mid_buf; | |
463 | struct buffer_head *left_buf; | |
464 | struct buffer_head *parent_buf = NULL; | |
465 | struct btrfs_node *right = NULL; | |
466 | struct btrfs_node *mid; | |
467 | struct btrfs_node *left = NULL; | |
468 | struct btrfs_node *parent = NULL; | |
469 | int ret = 0; | |
470 | int wret; | |
471 | int pslot; | |
472 | int orig_slot = path->slots[level]; | |
473 | u64 orig_ptr; | |
474 | ||
475 | if (level == 0) | |
476 | return 1; | |
477 | ||
478 | mid_buf = path->nodes[level]; | |
479 | mid = btrfs_buffer_node(mid_buf); | |
480 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); | |
481 | ||
482 | if (level < BTRFS_MAX_LEVEL - 1) | |
483 | parent_buf = path->nodes[level + 1]; | |
484 | pslot = path->slots[level + 1]; | |
485 | ||
486 | if (!parent_buf) | |
487 | return 1; | |
488 | parent = btrfs_buffer_node(parent_buf); | |
489 | ||
490 | left_buf = read_node_slot(root, parent_buf, pslot - 1); | |
491 | ||
492 | /* first, try to make some room in the middle buffer */ | |
493 | if (left_buf) { | |
494 | u32 left_nr; | |
495 | btrfs_cow_block(trans, root, left_buf, parent_buf, pslot - 1, | |
496 | &left_buf); | |
497 | left = btrfs_buffer_node(left_buf); | |
498 | left_nr = btrfs_header_nritems(&left->header); | |
499 | wret = push_node_left(trans, root, left_buf, mid_buf); | |
500 | if (wret < 0) | |
501 | ret = wret; | |
502 | if (wret == 0) { | |
503 | orig_slot += left_nr; | |
504 | btrfs_memcpy(root, parent, | |
505 | &parent->ptrs[pslot].key, | |
506 | &mid->ptrs[0].key, | |
507 | sizeof(struct btrfs_disk_key)); | |
508 | btrfs_mark_buffer_dirty(parent_buf); | |
509 | if (btrfs_header_nritems(&left->header) > orig_slot) { | |
510 | path->nodes[level] = left_buf; | |
511 | path->slots[level + 1] -= 1; | |
512 | path->slots[level] = orig_slot; | |
513 | btrfs_block_release(root, mid_buf); | |
514 | } else { | |
515 | orig_slot -= | |
516 | btrfs_header_nritems(&left->header); | |
517 | path->slots[level] = orig_slot; | |
518 | btrfs_block_release(root, left_buf); | |
519 | } | |
520 | check_node(root, path, level); | |
521 | return 0; | |
522 | } | |
523 | btrfs_block_release(root, left_buf); | |
524 | } | |
525 | right_buf = read_node_slot(root, parent_buf, pslot + 1); | |
526 | ||
527 | /* | |
528 | * then try to empty the right most buffer into the middle | |
529 | */ | |
530 | if (right_buf) { | |
531 | btrfs_cow_block(trans, root, right_buf, parent_buf, pslot + 1, | |
532 | &right_buf); | |
533 | right = btrfs_buffer_node(right_buf); | |
534 | wret = balance_node_right(trans, root, right_buf, mid_buf); | |
535 | if (wret < 0) | |
536 | ret = wret; | |
537 | if (wret == 0) { | |
538 | btrfs_memcpy(root, parent, | |
539 | &parent->ptrs[pslot + 1].key, | |
540 | &right->ptrs[0].key, | |
541 | sizeof(struct btrfs_disk_key)); | |
542 | btrfs_mark_buffer_dirty(parent_buf); | |
543 | if (btrfs_header_nritems(&mid->header) <= orig_slot) { | |
544 | path->nodes[level] = right_buf; | |
545 | path->slots[level + 1] += 1; | |
546 | path->slots[level] = orig_slot - | |
547 | btrfs_header_nritems(&mid->header); | |
548 | btrfs_block_release(root, mid_buf); | |
549 | } else { | |
550 | btrfs_block_release(root, right_buf); | |
551 | } | |
552 | check_node(root, path, level); | |
553 | return 0; | |
554 | } | |
555 | btrfs_block_release(root, right_buf); | |
556 | } | |
557 | check_node(root, path, level); | |
558 | return 1; | |
559 | } | |
560 | ||
74123bd7 CM |
561 | /* |
562 | * look for key in the tree. path is filled in with nodes along the way | |
563 | * if key is found, we return zero and you can find the item in the leaf | |
564 | * level of the path (level 0) | |
565 | * | |
566 | * If the key isn't found, the path points to the slot where it should | |
aa5d6bed CM |
567 | * be inserted, and 1 is returned. If there are other errors during the |
568 | * search a negative error number is returned. | |
97571fd0 CM |
569 | * |
570 | * if ins_len > 0, nodes and leaves will be split as we walk down the | |
571 | * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if | |
572 | * possible) | |
74123bd7 | 573 | */ |
e089f05c CM |
574 | int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root |
575 | *root, struct btrfs_key *key, struct btrfs_path *p, int | |
576 | ins_len, int cow) | |
be0e5c09 | 577 | { |
e20d96d6 CM |
578 | struct buffer_head *b; |
579 | struct buffer_head *cow_buf; | |
234b63a0 | 580 | struct btrfs_node *c; |
be0e5c09 CM |
581 | int slot; |
582 | int ret; | |
583 | int level; | |
5c680ed6 | 584 | |
22b0ebda CM |
585 | WARN_ON(p->nodes[0] != NULL); |
586 | WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex)); | |
bb803951 CM |
587 | again: |
588 | b = root->node; | |
e20d96d6 | 589 | get_bh(b); |
eb60ceac | 590 | while (b) { |
e20d96d6 CM |
591 | c = btrfs_buffer_node(b); |
592 | level = btrfs_header_level(&c->header); | |
02217ed2 CM |
593 | if (cow) { |
594 | int wret; | |
e20d96d6 CM |
595 | wret = btrfs_cow_block(trans, root, b, |
596 | p->nodes[level + 1], | |
597 | p->slots[level + 1], | |
e089f05c | 598 | &cow_buf); |
02217ed2 | 599 | b = cow_buf; |
2c90e5d6 | 600 | c = btrfs_buffer_node(b); |
02217ed2 CM |
601 | } |
602 | BUG_ON(!cow && ins_len); | |
2c90e5d6 CM |
603 | if (level != btrfs_header_level(&c->header)) |
604 | WARN_ON(1); | |
605 | level = btrfs_header_level(&c->header); | |
eb60ceac | 606 | p->nodes[level] = b; |
123abc88 | 607 | ret = check_block(root, p, level); |
aa5d6bed CM |
608 | if (ret) |
609 | return -1; | |
be0e5c09 | 610 | ret = bin_search(c, key, &slot); |
7518a238 | 611 | if (!btrfs_is_leaf(c)) { |
be0e5c09 CM |
612 | if (ret && slot > 0) |
613 | slot -= 1; | |
614 | p->slots[level] = slot; | |
d4dbff95 CM |
615 | if (ins_len > 0 && btrfs_header_nritems(&c->header) >= |
616 | BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { | |
e089f05c | 617 | int sret = split_node(trans, root, p, level); |
5c680ed6 CM |
618 | BUG_ON(sret > 0); |
619 | if (sret) | |
620 | return sret; | |
621 | b = p->nodes[level]; | |
e20d96d6 | 622 | c = btrfs_buffer_node(b); |
5c680ed6 | 623 | slot = p->slots[level]; |
bb803951 | 624 | } else if (ins_len < 0) { |
e089f05c CM |
625 | int sret = balance_level(trans, root, p, |
626 | level); | |
bb803951 CM |
627 | if (sret) |
628 | return sret; | |
629 | b = p->nodes[level]; | |
630 | if (!b) | |
631 | goto again; | |
e20d96d6 | 632 | c = btrfs_buffer_node(b); |
bb803951 | 633 | slot = p->slots[level]; |
7518a238 | 634 | BUG_ON(btrfs_header_nritems(&c->header) == 1); |
5c680ed6 | 635 | } |
1d4f8a0c | 636 | b = read_tree_block(root, btrfs_node_blockptr(c, slot)); |
be0e5c09 | 637 | } else { |
234b63a0 | 638 | struct btrfs_leaf *l = (struct btrfs_leaf *)c; |
be0e5c09 | 639 | p->slots[level] = slot; |
123abc88 | 640 | if (ins_len > 0 && btrfs_leaf_free_space(root, l) < |
0783fcfc | 641 | sizeof(struct btrfs_item) + ins_len) { |
d4dbff95 CM |
642 | int sret = split_leaf(trans, root, key, |
643 | p, ins_len); | |
5c680ed6 CM |
644 | BUG_ON(sret > 0); |
645 | if (sret) | |
646 | return sret; | |
647 | } | |
be0e5c09 CM |
648 | return ret; |
649 | } | |
650 | } | |
aa5d6bed | 651 | return 1; |
be0e5c09 CM |
652 | } |
653 | ||
74123bd7 CM |
654 | /* |
655 | * adjust the pointers going up the tree, starting at level | |
656 | * making sure the right key of each node is points to 'key'. | |
657 | * This is used after shifting pointers to the left, so it stops | |
658 | * fixing up pointers when a given leaf/node is not in slot 0 of the | |
659 | * higher levels | |
aa5d6bed CM |
660 | * |
661 | * If this fails to write a tree block, it returns -1, but continues | |
662 | * fixing up the blocks in ram so the tree is consistent. | |
74123bd7 | 663 | */ |
e089f05c CM |
664 | static int fixup_low_keys(struct btrfs_trans_handle *trans, struct btrfs_root |
665 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
666 | *key, int level) | |
be0e5c09 CM |
667 | { |
668 | int i; | |
aa5d6bed | 669 | int ret = 0; |
234b63a0 CM |
670 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
671 | struct btrfs_node *t; | |
be0e5c09 | 672 | int tslot = path->slots[i]; |
eb60ceac | 673 | if (!path->nodes[i]) |
be0e5c09 | 674 | break; |
e20d96d6 | 675 | t = btrfs_buffer_node(path->nodes[i]); |
d6025579 CM |
676 | btrfs_memcpy(root, t, &t->ptrs[tslot].key, key, sizeof(*key)); |
677 | btrfs_mark_buffer_dirty(path->nodes[i]); | |
be0e5c09 CM |
678 | if (tslot != 0) |
679 | break; | |
680 | } | |
aa5d6bed | 681 | return ret; |
be0e5c09 CM |
682 | } |
683 | ||
74123bd7 CM |
684 | /* |
685 | * try to push data from one node into the next node left in the | |
79f95c82 | 686 | * tree. |
aa5d6bed CM |
687 | * |
688 | * returns 0 if some ptrs were pushed left, < 0 if there was some horrible | |
689 | * error, and > 0 if there was no room in the left hand block. | |
74123bd7 | 690 | */ |
e089f05c | 691 | static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root |
e20d96d6 CM |
692 | *root, struct buffer_head *dst_buf, struct |
693 | buffer_head *src_buf) | |
be0e5c09 | 694 | { |
e20d96d6 CM |
695 | struct btrfs_node *src = btrfs_buffer_node(src_buf); |
696 | struct btrfs_node *dst = btrfs_buffer_node(dst_buf); | |
be0e5c09 | 697 | int push_items = 0; |
bb803951 CM |
698 | int src_nritems; |
699 | int dst_nritems; | |
aa5d6bed | 700 | int ret = 0; |
be0e5c09 | 701 | |
7518a238 CM |
702 | src_nritems = btrfs_header_nritems(&src->header); |
703 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 704 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
eb60ceac | 705 | if (push_items <= 0) { |
be0e5c09 | 706 | return 1; |
eb60ceac | 707 | } |
be0e5c09 | 708 | |
bb803951 | 709 | if (src_nritems < push_items) |
79f95c82 CM |
710 | push_items = src_nritems; |
711 | ||
d6025579 CM |
712 | btrfs_memcpy(root, dst, dst->ptrs + dst_nritems, src->ptrs, |
713 | push_items * sizeof(struct btrfs_key_ptr)); | |
bb803951 | 714 | if (push_items < src_nritems) { |
d6025579 | 715 | btrfs_memmove(root, src, src->ptrs, src->ptrs + push_items, |
e2fa7227 | 716 | (src_nritems - push_items) * |
123abc88 | 717 | sizeof(struct btrfs_key_ptr)); |
bb803951 | 718 | } |
7518a238 CM |
719 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
720 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
d6025579 CM |
721 | btrfs_mark_buffer_dirty(src_buf); |
722 | btrfs_mark_buffer_dirty(dst_buf); | |
79f95c82 CM |
723 | return ret; |
724 | } | |
725 | ||
726 | /* | |
727 | * try to push data from one node into the next node right in the | |
728 | * tree. | |
729 | * | |
730 | * returns 0 if some ptrs were pushed, < 0 if there was some horrible | |
731 | * error, and > 0 if there was no room in the right hand block. | |
732 | * | |
733 | * this will only push up to 1/2 the contents of the left node over | |
734 | */ | |
e089f05c | 735 | static int balance_node_right(struct btrfs_trans_handle *trans, struct |
e20d96d6 CM |
736 | btrfs_root *root, struct buffer_head *dst_buf, |
737 | struct buffer_head *src_buf) | |
79f95c82 | 738 | { |
e20d96d6 CM |
739 | struct btrfs_node *src = btrfs_buffer_node(src_buf); |
740 | struct btrfs_node *dst = btrfs_buffer_node(dst_buf); | |
79f95c82 CM |
741 | int push_items = 0; |
742 | int max_push; | |
743 | int src_nritems; | |
744 | int dst_nritems; | |
745 | int ret = 0; | |
79f95c82 | 746 | |
7518a238 CM |
747 | src_nritems = btrfs_header_nritems(&src->header); |
748 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 749 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
79f95c82 CM |
750 | if (push_items <= 0) { |
751 | return 1; | |
752 | } | |
753 | ||
754 | max_push = src_nritems / 2 + 1; | |
755 | /* don't try to empty the node */ | |
756 | if (max_push > src_nritems) | |
757 | return 1; | |
758 | if (max_push < push_items) | |
759 | push_items = max_push; | |
760 | ||
d6025579 CM |
761 | btrfs_memmove(root, dst, dst->ptrs + push_items, dst->ptrs, |
762 | dst_nritems * sizeof(struct btrfs_key_ptr)); | |
763 | ||
764 | btrfs_memcpy(root, dst, dst->ptrs, | |
765 | src->ptrs + src_nritems - push_items, | |
766 | push_items * sizeof(struct btrfs_key_ptr)); | |
79f95c82 | 767 | |
7518a238 CM |
768 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
769 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
79f95c82 | 770 | |
d6025579 CM |
771 | btrfs_mark_buffer_dirty(src_buf); |
772 | btrfs_mark_buffer_dirty(dst_buf); | |
aa5d6bed | 773 | return ret; |
be0e5c09 CM |
774 | } |
775 | ||
97571fd0 CM |
776 | /* |
777 | * helper function to insert a new root level in the tree. | |
778 | * A new node is allocated, and a single item is inserted to | |
779 | * point to the existing root | |
aa5d6bed CM |
780 | * |
781 | * returns zero on success or < 0 on failure. | |
97571fd0 | 782 | */ |
e089f05c CM |
783 | static int insert_new_root(struct btrfs_trans_handle *trans, struct btrfs_root |
784 | *root, struct btrfs_path *path, int level) | |
5c680ed6 | 785 | { |
e20d96d6 | 786 | struct buffer_head *t; |
234b63a0 CM |
787 | struct btrfs_node *lower; |
788 | struct btrfs_node *c; | |
e2fa7227 | 789 | struct btrfs_disk_key *lower_key; |
5c680ed6 CM |
790 | |
791 | BUG_ON(path->nodes[level]); | |
792 | BUG_ON(path->nodes[level-1] != root->node); | |
793 | ||
e089f05c | 794 | t = btrfs_alloc_free_block(trans, root); |
e20d96d6 | 795 | c = btrfs_buffer_node(t); |
123abc88 | 796 | memset(c, 0, root->blocksize); |
7518a238 CM |
797 | btrfs_set_header_nritems(&c->header, 1); |
798 | btrfs_set_header_level(&c->header, level); | |
7eccb903 | 799 | btrfs_set_header_blocknr(&c->header, bh_blocknr(t)); |
7f5c1516 | 800 | btrfs_set_header_generation(&c->header, trans->transid); |
e20d96d6 | 801 | lower = btrfs_buffer_node(path->nodes[level-1]); |
3eb0314d CM |
802 | memcpy(c->header.fsid, root->fs_info->disk_super->fsid, |
803 | sizeof(c->header.fsid)); | |
7518a238 | 804 | if (btrfs_is_leaf(lower)) |
234b63a0 | 805 | lower_key = &((struct btrfs_leaf *)lower)->items[0].key; |
5c680ed6 | 806 | else |
123abc88 | 807 | lower_key = &lower->ptrs[0].key; |
d6025579 CM |
808 | btrfs_memcpy(root, c, &c->ptrs[0].key, lower_key, |
809 | sizeof(struct btrfs_disk_key)); | |
7eccb903 | 810 | btrfs_set_node_blockptr(c, 0, bh_blocknr(path->nodes[level - 1])); |
d5719762 | 811 | |
d6025579 | 812 | btrfs_mark_buffer_dirty(t); |
d5719762 | 813 | |
5c680ed6 | 814 | /* the super has an extra ref to root->node */ |
234b63a0 | 815 | btrfs_block_release(root, root->node); |
5c680ed6 | 816 | root->node = t; |
e20d96d6 | 817 | get_bh(t); |
5c680ed6 CM |
818 | path->nodes[level] = t; |
819 | path->slots[level] = 0; | |
820 | return 0; | |
821 | } | |
822 | ||
74123bd7 CM |
823 | /* |
824 | * worker function to insert a single pointer in a node. | |
825 | * the node should have enough room for the pointer already | |
97571fd0 | 826 | * |
74123bd7 CM |
827 | * slot and level indicate where you want the key to go, and |
828 | * blocknr is the block the key points to. | |
aa5d6bed CM |
829 | * |
830 | * returns zero on success and < 0 on any error | |
74123bd7 | 831 | */ |
e089f05c CM |
832 | static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root |
833 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
834 | *key, u64 blocknr, int slot, int level) | |
74123bd7 | 835 | { |
234b63a0 | 836 | struct btrfs_node *lower; |
74123bd7 | 837 | int nritems; |
5c680ed6 CM |
838 | |
839 | BUG_ON(!path->nodes[level]); | |
e20d96d6 | 840 | lower = btrfs_buffer_node(path->nodes[level]); |
7518a238 | 841 | nritems = btrfs_header_nritems(&lower->header); |
74123bd7 CM |
842 | if (slot > nritems) |
843 | BUG(); | |
123abc88 | 844 | if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root)) |
74123bd7 CM |
845 | BUG(); |
846 | if (slot != nritems) { | |
d6025579 CM |
847 | btrfs_memmove(root, lower, lower->ptrs + slot + 1, |
848 | lower->ptrs + slot, | |
849 | (nritems - slot) * sizeof(struct btrfs_key_ptr)); | |
74123bd7 | 850 | } |
d6025579 CM |
851 | btrfs_memcpy(root, lower, &lower->ptrs[slot].key, |
852 | key, sizeof(struct btrfs_disk_key)); | |
1d4f8a0c | 853 | btrfs_set_node_blockptr(lower, slot, blocknr); |
7518a238 | 854 | btrfs_set_header_nritems(&lower->header, nritems + 1); |
d6025579 | 855 | btrfs_mark_buffer_dirty(path->nodes[level]); |
74123bd7 CM |
856 | return 0; |
857 | } | |
858 | ||
97571fd0 CM |
859 | /* |
860 | * split the node at the specified level in path in two. | |
861 | * The path is corrected to point to the appropriate node after the split | |
862 | * | |
863 | * Before splitting this tries to make some room in the node by pushing | |
864 | * left and right, if either one works, it returns right away. | |
aa5d6bed CM |
865 | * |
866 | * returns 0 on success and < 0 on failure | |
97571fd0 | 867 | */ |
e089f05c CM |
868 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
869 | *root, struct btrfs_path *path, int level) | |
be0e5c09 | 870 | { |
e20d96d6 | 871 | struct buffer_head *t; |
234b63a0 | 872 | struct btrfs_node *c; |
e20d96d6 | 873 | struct buffer_head *split_buffer; |
234b63a0 | 874 | struct btrfs_node *split; |
be0e5c09 | 875 | int mid; |
5c680ed6 | 876 | int ret; |
aa5d6bed | 877 | int wret; |
7518a238 | 878 | u32 c_nritems; |
eb60ceac | 879 | |
5c680ed6 | 880 | t = path->nodes[level]; |
e20d96d6 | 881 | c = btrfs_buffer_node(t); |
5c680ed6 CM |
882 | if (t == root->node) { |
883 | /* trying to split the root, lets make a new one */ | |
e089f05c | 884 | ret = insert_new_root(trans, root, path, level + 1); |
5c680ed6 CM |
885 | if (ret) |
886 | return ret; | |
e66f709b CM |
887 | } else { |
888 | ret = push_nodes_for_insert(trans, root, path, level); | |
889 | t = path->nodes[level]; | |
890 | c = btrfs_buffer_node(t); | |
891 | if (!ret && | |
892 | btrfs_header_nritems(&c->header) < | |
893 | BTRFS_NODEPTRS_PER_BLOCK(root) - 1) | |
894 | return 0; | |
be0e5c09 | 895 | } |
e66f709b | 896 | |
7518a238 | 897 | c_nritems = btrfs_header_nritems(&c->header); |
e089f05c | 898 | split_buffer = btrfs_alloc_free_block(trans, root); |
e20d96d6 | 899 | split = btrfs_buffer_node(split_buffer); |
7518a238 | 900 | btrfs_set_header_flags(&split->header, btrfs_header_flags(&c->header)); |
9a6f11ed | 901 | btrfs_set_header_level(&split->header, btrfs_header_level(&c->header)); |
7eccb903 | 902 | btrfs_set_header_blocknr(&split->header, bh_blocknr(split_buffer)); |
7f5c1516 | 903 | btrfs_set_header_generation(&split->header, trans->transid); |
3eb0314d CM |
904 | memcpy(split->header.fsid, root->fs_info->disk_super->fsid, |
905 | sizeof(split->header.fsid)); | |
7518a238 | 906 | mid = (c_nritems + 1) / 2; |
d6025579 CM |
907 | btrfs_memcpy(root, split, split->ptrs, c->ptrs + mid, |
908 | (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); | |
7518a238 CM |
909 | btrfs_set_header_nritems(&split->header, c_nritems - mid); |
910 | btrfs_set_header_nritems(&c->header, mid); | |
aa5d6bed CM |
911 | ret = 0; |
912 | ||
d6025579 CM |
913 | btrfs_mark_buffer_dirty(t); |
914 | btrfs_mark_buffer_dirty(split_buffer); | |
e089f05c | 915 | wret = insert_ptr(trans, root, path, &split->ptrs[0].key, |
7eccb903 | 916 | bh_blocknr(split_buffer), path->slots[level + 1] + 1, |
123abc88 | 917 | level + 1); |
aa5d6bed CM |
918 | if (wret) |
919 | ret = wret; | |
920 | ||
5de08d7d | 921 | if (path->slots[level] >= mid) { |
5c680ed6 | 922 | path->slots[level] -= mid; |
234b63a0 | 923 | btrfs_block_release(root, t); |
5c680ed6 CM |
924 | path->nodes[level] = split_buffer; |
925 | path->slots[level + 1] += 1; | |
926 | } else { | |
234b63a0 | 927 | btrfs_block_release(root, split_buffer); |
be0e5c09 | 928 | } |
aa5d6bed | 929 | return ret; |
be0e5c09 CM |
930 | } |
931 | ||
74123bd7 CM |
932 | /* |
933 | * how many bytes are required to store the items in a leaf. start | |
934 | * and nr indicate which items in the leaf to check. This totals up the | |
935 | * space used both by the item structs and the item data | |
936 | */ | |
234b63a0 | 937 | static int leaf_space_used(struct btrfs_leaf *l, int start, int nr) |
be0e5c09 CM |
938 | { |
939 | int data_len; | |
d4dbff95 CM |
940 | int nritems = btrfs_header_nritems(&l->header); |
941 | int end = min(nritems, start + nr) - 1; | |
be0e5c09 CM |
942 | |
943 | if (!nr) | |
944 | return 0; | |
0783fcfc CM |
945 | data_len = btrfs_item_end(l->items + start); |
946 | data_len = data_len - btrfs_item_offset(l->items + end); | |
947 | data_len += sizeof(struct btrfs_item) * nr; | |
d4dbff95 | 948 | WARN_ON(data_len < 0); |
be0e5c09 CM |
949 | return data_len; |
950 | } | |
951 | ||
d4dbff95 CM |
952 | /* |
953 | * The space between the end of the leaf items and | |
954 | * the start of the leaf data. IOW, how much room | |
955 | * the leaf has left for both items and data | |
956 | */ | |
957 | int btrfs_leaf_free_space(struct btrfs_root *root, struct btrfs_leaf *leaf) | |
958 | { | |
959 | int nritems = btrfs_header_nritems(&leaf->header); | |
960 | return BTRFS_LEAF_DATA_SIZE(root) - leaf_space_used(leaf, 0, nritems); | |
961 | } | |
962 | ||
00ec4c51 CM |
963 | /* |
964 | * push some data in the path leaf to the right, trying to free up at | |
965 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
aa5d6bed CM |
966 | * |
967 | * returns 1 if the push failed because the other node didn't have enough | |
968 | * room, 0 if everything worked out and < 0 if there were major errors. | |
00ec4c51 | 969 | */ |
e089f05c CM |
970 | static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root |
971 | *root, struct btrfs_path *path, int data_size) | |
00ec4c51 | 972 | { |
e20d96d6 CM |
973 | struct buffer_head *left_buf = path->nodes[0]; |
974 | struct btrfs_leaf *left = btrfs_buffer_leaf(left_buf); | |
234b63a0 | 975 | struct btrfs_leaf *right; |
e20d96d6 CM |
976 | struct buffer_head *right_buf; |
977 | struct buffer_head *upper; | |
978 | struct btrfs_node *upper_node; | |
00ec4c51 CM |
979 | int slot; |
980 | int i; | |
981 | int free_space; | |
982 | int push_space = 0; | |
983 | int push_items = 0; | |
0783fcfc | 984 | struct btrfs_item *item; |
7518a238 CM |
985 | u32 left_nritems; |
986 | u32 right_nritems; | |
00ec4c51 CM |
987 | |
988 | slot = path->slots[1]; | |
989 | if (!path->nodes[1]) { | |
990 | return 1; | |
991 | } | |
992 | upper = path->nodes[1]; | |
e20d96d6 CM |
993 | upper_node = btrfs_buffer_node(upper); |
994 | if (slot >= btrfs_header_nritems(&upper_node->header) - 1) { | |
00ec4c51 CM |
995 | return 1; |
996 | } | |
e20d96d6 CM |
997 | right_buf = read_tree_block(root, |
998 | btrfs_node_blockptr(btrfs_buffer_node(upper), slot + 1)); | |
999 | right = btrfs_buffer_leaf(right_buf); | |
123abc88 | 1000 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 1001 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1002 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
1003 | return 1; |
1004 | } | |
02217ed2 | 1005 | /* cow and double check */ |
e089f05c | 1006 | btrfs_cow_block(trans, root, right_buf, upper, slot + 1, &right_buf); |
e20d96d6 | 1007 | right = btrfs_buffer_leaf(right_buf); |
123abc88 | 1008 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 1009 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1010 | btrfs_block_release(root, right_buf); |
02217ed2 CM |
1011 | return 1; |
1012 | } | |
1013 | ||
7518a238 | 1014 | left_nritems = btrfs_header_nritems(&left->header); |
a429e513 CM |
1015 | if (left_nritems == 0) { |
1016 | btrfs_block_release(root, right_buf); | |
1017 | return 1; | |
1018 | } | |
1019 | for (i = left_nritems - 1; i >= 1; i--) { | |
00ec4c51 CM |
1020 | item = left->items + i; |
1021 | if (path->slots[0] == i) | |
1022 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
1023 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
1024 | free_space) | |
00ec4c51 CM |
1025 | break; |
1026 | push_items++; | |
0783fcfc | 1027 | push_space += btrfs_item_size(item) + sizeof(*item); |
00ec4c51 CM |
1028 | } |
1029 | if (push_items == 0) { | |
234b63a0 | 1030 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
1031 | return 1; |
1032 | } | |
a429e513 CM |
1033 | if (push_items == left_nritems) |
1034 | WARN_ON(1); | |
7518a238 | 1035 | right_nritems = btrfs_header_nritems(&right->header); |
00ec4c51 | 1036 | /* push left to right */ |
0783fcfc | 1037 | push_space = btrfs_item_end(left->items + left_nritems - push_items); |
123abc88 | 1038 | push_space -= leaf_data_end(root, left); |
00ec4c51 | 1039 | /* make room in the right data area */ |
d6025579 CM |
1040 | btrfs_memmove(root, right, btrfs_leaf_data(right) + |
1041 | leaf_data_end(root, right) - push_space, | |
1042 | btrfs_leaf_data(right) + | |
1043 | leaf_data_end(root, right), BTRFS_LEAF_DATA_SIZE(root) - | |
1044 | leaf_data_end(root, right)); | |
00ec4c51 | 1045 | /* copy from the left data area */ |
d6025579 CM |
1046 | btrfs_memcpy(root, right, btrfs_leaf_data(right) + |
1047 | BTRFS_LEAF_DATA_SIZE(root) - push_space, | |
1048 | btrfs_leaf_data(left) + leaf_data_end(root, left), | |
1049 | push_space); | |
1050 | btrfs_memmove(root, right, right->items + push_items, right->items, | |
0783fcfc | 1051 | right_nritems * sizeof(struct btrfs_item)); |
00ec4c51 | 1052 | /* copy the items from left to right */ |
d6025579 CM |
1053 | btrfs_memcpy(root, right, right->items, left->items + |
1054 | left_nritems - push_items, | |
1055 | push_items * sizeof(struct btrfs_item)); | |
00ec4c51 CM |
1056 | |
1057 | /* update the item pointers */ | |
7518a238 CM |
1058 | right_nritems += push_items; |
1059 | btrfs_set_header_nritems(&right->header, right_nritems); | |
123abc88 | 1060 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
7518a238 | 1061 | for (i = 0; i < right_nritems; i++) { |
0783fcfc CM |
1062 | btrfs_set_item_offset(right->items + i, push_space - |
1063 | btrfs_item_size(right->items + i)); | |
1064 | push_space = btrfs_item_offset(right->items + i); | |
00ec4c51 | 1065 | } |
7518a238 CM |
1066 | left_nritems -= push_items; |
1067 | btrfs_set_header_nritems(&left->header, left_nritems); | |
00ec4c51 | 1068 | |
d6025579 CM |
1069 | btrfs_mark_buffer_dirty(left_buf); |
1070 | btrfs_mark_buffer_dirty(right_buf); | |
a429e513 | 1071 | |
d6025579 | 1072 | btrfs_memcpy(root, upper_node, &upper_node->ptrs[slot + 1].key, |
e2fa7227 | 1073 | &right->items[0].key, sizeof(struct btrfs_disk_key)); |
d6025579 | 1074 | btrfs_mark_buffer_dirty(upper); |
02217ed2 | 1075 | |
00ec4c51 | 1076 | /* then fixup the leaf pointer in the path */ |
7518a238 CM |
1077 | if (path->slots[0] >= left_nritems) { |
1078 | path->slots[0] -= left_nritems; | |
234b63a0 | 1079 | btrfs_block_release(root, path->nodes[0]); |
00ec4c51 CM |
1080 | path->nodes[0] = right_buf; |
1081 | path->slots[1] += 1; | |
1082 | } else { | |
234b63a0 | 1083 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
1084 | } |
1085 | return 0; | |
1086 | } | |
74123bd7 CM |
1087 | /* |
1088 | * push some data in the path leaf to the left, trying to free up at | |
1089 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
1090 | */ | |
e089f05c CM |
1091 | static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root |
1092 | *root, struct btrfs_path *path, int data_size) | |
be0e5c09 | 1093 | { |
e20d96d6 CM |
1094 | struct buffer_head *right_buf = path->nodes[0]; |
1095 | struct btrfs_leaf *right = btrfs_buffer_leaf(right_buf); | |
1096 | struct buffer_head *t; | |
234b63a0 | 1097 | struct btrfs_leaf *left; |
be0e5c09 CM |
1098 | int slot; |
1099 | int i; | |
1100 | int free_space; | |
1101 | int push_space = 0; | |
1102 | int push_items = 0; | |
0783fcfc | 1103 | struct btrfs_item *item; |
7518a238 | 1104 | u32 old_left_nritems; |
aa5d6bed CM |
1105 | int ret = 0; |
1106 | int wret; | |
be0e5c09 CM |
1107 | |
1108 | slot = path->slots[1]; | |
1109 | if (slot == 0) { | |
1110 | return 1; | |
1111 | } | |
1112 | if (!path->nodes[1]) { | |
1113 | return 1; | |
1114 | } | |
e20d96d6 CM |
1115 | t = read_tree_block(root, |
1116 | btrfs_node_blockptr(btrfs_buffer_node(path->nodes[1]), slot - 1)); | |
1117 | left = btrfs_buffer_leaf(t); | |
123abc88 | 1118 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 1119 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1120 | btrfs_block_release(root, t); |
be0e5c09 CM |
1121 | return 1; |
1122 | } | |
02217ed2 CM |
1123 | |
1124 | /* cow and double check */ | |
e089f05c | 1125 | btrfs_cow_block(trans, root, t, path->nodes[1], slot - 1, &t); |
e20d96d6 | 1126 | left = btrfs_buffer_leaf(t); |
123abc88 | 1127 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 1128 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1129 | btrfs_block_release(root, t); |
02217ed2 CM |
1130 | return 1; |
1131 | } | |
1132 | ||
a429e513 CM |
1133 | if (btrfs_header_nritems(&right->header) == 0) { |
1134 | btrfs_block_release(root, t); | |
1135 | return 1; | |
1136 | } | |
1137 | ||
1138 | for (i = 0; i < btrfs_header_nritems(&right->header) - 1; i++) { | |
be0e5c09 CM |
1139 | item = right->items + i; |
1140 | if (path->slots[0] == i) | |
1141 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
1142 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
1143 | free_space) | |
be0e5c09 CM |
1144 | break; |
1145 | push_items++; | |
0783fcfc | 1146 | push_space += btrfs_item_size(item) + sizeof(*item); |
be0e5c09 CM |
1147 | } |
1148 | if (push_items == 0) { | |
234b63a0 | 1149 | btrfs_block_release(root, t); |
be0e5c09 CM |
1150 | return 1; |
1151 | } | |
a429e513 CM |
1152 | if (push_items == btrfs_header_nritems(&right->header)) |
1153 | WARN_ON(1); | |
be0e5c09 | 1154 | /* push data from right to left */ |
d6025579 CM |
1155 | btrfs_memcpy(root, left, left->items + |
1156 | btrfs_header_nritems(&left->header), | |
1157 | right->items, push_items * sizeof(struct btrfs_item)); | |
123abc88 | 1158 | push_space = BTRFS_LEAF_DATA_SIZE(root) - |
0783fcfc | 1159 | btrfs_item_offset(right->items + push_items -1); |
d6025579 CM |
1160 | btrfs_memcpy(root, left, btrfs_leaf_data(left) + |
1161 | leaf_data_end(root, left) - push_space, | |
1162 | btrfs_leaf_data(right) + | |
1163 | btrfs_item_offset(right->items + push_items - 1), | |
1164 | push_space); | |
7518a238 | 1165 | old_left_nritems = btrfs_header_nritems(&left->header); |
eb60ceac CM |
1166 | BUG_ON(old_left_nritems < 0); |
1167 | ||
0783fcfc | 1168 | for (i = old_left_nritems; i < old_left_nritems + push_items; i++) { |
123abc88 CM |
1169 | u32 ioff = btrfs_item_offset(left->items + i); |
1170 | btrfs_set_item_offset(left->items + i, ioff - | |
1171 | (BTRFS_LEAF_DATA_SIZE(root) - | |
0783fcfc CM |
1172 | btrfs_item_offset(left->items + |
1173 | old_left_nritems - 1))); | |
be0e5c09 | 1174 | } |
7518a238 | 1175 | btrfs_set_header_nritems(&left->header, old_left_nritems + push_items); |
be0e5c09 CM |
1176 | |
1177 | /* fixup right node */ | |
0783fcfc | 1178 | push_space = btrfs_item_offset(right->items + push_items - 1) - |
123abc88 | 1179 | leaf_data_end(root, right); |
d6025579 CM |
1180 | btrfs_memmove(root, right, btrfs_leaf_data(right) + |
1181 | BTRFS_LEAF_DATA_SIZE(root) - push_space, | |
1182 | btrfs_leaf_data(right) + | |
1183 | leaf_data_end(root, right), push_space); | |
1184 | btrfs_memmove(root, right, right->items, right->items + push_items, | |
7518a238 | 1185 | (btrfs_header_nritems(&right->header) - push_items) * |
0783fcfc | 1186 | sizeof(struct btrfs_item)); |
7518a238 CM |
1187 | btrfs_set_header_nritems(&right->header, |
1188 | btrfs_header_nritems(&right->header) - | |
1189 | push_items); | |
123abc88 | 1190 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
eb60ceac | 1191 | |
7518a238 | 1192 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
0783fcfc CM |
1193 | btrfs_set_item_offset(right->items + i, push_space - |
1194 | btrfs_item_size(right->items + i)); | |
1195 | push_space = btrfs_item_offset(right->items + i); | |
be0e5c09 | 1196 | } |
eb60ceac | 1197 | |
d6025579 CM |
1198 | btrfs_mark_buffer_dirty(t); |
1199 | btrfs_mark_buffer_dirty(right_buf); | |
e089f05c | 1200 | wret = fixup_low_keys(trans, root, path, &right->items[0].key, 1); |
aa5d6bed CM |
1201 | if (wret) |
1202 | ret = wret; | |
be0e5c09 CM |
1203 | |
1204 | /* then fixup the leaf pointer in the path */ | |
1205 | if (path->slots[0] < push_items) { | |
1206 | path->slots[0] += old_left_nritems; | |
234b63a0 | 1207 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1208 | path->nodes[0] = t; |
be0e5c09 CM |
1209 | path->slots[1] -= 1; |
1210 | } else { | |
234b63a0 | 1211 | btrfs_block_release(root, t); |
be0e5c09 CM |
1212 | path->slots[0] -= push_items; |
1213 | } | |
eb60ceac | 1214 | BUG_ON(path->slots[0] < 0); |
aa5d6bed | 1215 | return ret; |
be0e5c09 CM |
1216 | } |
1217 | ||
74123bd7 CM |
1218 | /* |
1219 | * split the path's leaf in two, making sure there is at least data_size | |
1220 | * available for the resulting leaf level of the path. | |
aa5d6bed CM |
1221 | * |
1222 | * returns 0 if all went well and < 0 on failure. | |
74123bd7 | 1223 | */ |
e089f05c | 1224 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root |
d4dbff95 CM |
1225 | *root, struct btrfs_key *ins_key, |
1226 | struct btrfs_path *path, int data_size) | |
be0e5c09 | 1227 | { |
e20d96d6 | 1228 | struct buffer_head *l_buf; |
234b63a0 | 1229 | struct btrfs_leaf *l; |
7518a238 | 1230 | u32 nritems; |
eb60ceac CM |
1231 | int mid; |
1232 | int slot; | |
234b63a0 | 1233 | struct btrfs_leaf *right; |
e20d96d6 | 1234 | struct buffer_head *right_buffer; |
0783fcfc | 1235 | int space_needed = data_size + sizeof(struct btrfs_item); |
be0e5c09 CM |
1236 | int data_copy_size; |
1237 | int rt_data_off; | |
1238 | int i; | |
d4dbff95 | 1239 | int ret = 0; |
aa5d6bed | 1240 | int wret; |
d4dbff95 CM |
1241 | int double_split = 0; |
1242 | struct btrfs_disk_key disk_key; | |
aa5d6bed | 1243 | |
40689478 | 1244 | /* first try to make some room by pushing left and right */ |
e089f05c | 1245 | wret = push_leaf_left(trans, root, path, data_size); |
eaee50e8 CM |
1246 | if (wret < 0) |
1247 | return wret; | |
1248 | if (wret) { | |
e089f05c | 1249 | wret = push_leaf_right(trans, root, path, data_size); |
eaee50e8 CM |
1250 | if (wret < 0) |
1251 | return wret; | |
1252 | } | |
aa5d6bed | 1253 | l_buf = path->nodes[0]; |
e20d96d6 | 1254 | l = btrfs_buffer_leaf(l_buf); |
aa5d6bed CM |
1255 | |
1256 | /* did the pushes work? */ | |
123abc88 CM |
1257 | if (btrfs_leaf_free_space(root, l) >= |
1258 | sizeof(struct btrfs_item) + data_size) | |
aa5d6bed CM |
1259 | return 0; |
1260 | ||
5c680ed6 | 1261 | if (!path->nodes[1]) { |
e089f05c | 1262 | ret = insert_new_root(trans, root, path, 1); |
5c680ed6 CM |
1263 | if (ret) |
1264 | return ret; | |
1265 | } | |
eb60ceac | 1266 | slot = path->slots[0]; |
7518a238 | 1267 | nritems = btrfs_header_nritems(&l->header); |
eb60ceac | 1268 | mid = (nritems + 1)/ 2; |
e089f05c | 1269 | right_buffer = btrfs_alloc_free_block(trans, root); |
eb60ceac | 1270 | BUG_ON(!right_buffer); |
e20d96d6 | 1271 | right = btrfs_buffer_leaf(right_buffer); |
123abc88 | 1272 | memset(&right->header, 0, sizeof(right->header)); |
7eccb903 | 1273 | btrfs_set_header_blocknr(&right->header, bh_blocknr(right_buffer)); |
7f5c1516 | 1274 | btrfs_set_header_generation(&right->header, trans->transid); |
7518a238 | 1275 | btrfs_set_header_level(&right->header, 0); |
3eb0314d CM |
1276 | memcpy(right->header.fsid, root->fs_info->disk_super->fsid, |
1277 | sizeof(right->header.fsid)); | |
d4dbff95 CM |
1278 | if (mid <= slot) { |
1279 | if (nritems == 1 || | |
1280 | leaf_space_used(l, mid, nritems - mid) + space_needed > | |
1281 | BTRFS_LEAF_DATA_SIZE(root)) { | |
1282 | if (slot >= nritems) { | |
1283 | btrfs_cpu_key_to_disk(&disk_key, ins_key); | |
1284 | btrfs_set_header_nritems(&right->header, 0); | |
1285 | wret = insert_ptr(trans, root, path, | |
1286 | &disk_key, | |
7eccb903 | 1287 | bh_blocknr(right_buffer), |
d4dbff95 CM |
1288 | path->slots[1] + 1, 1); |
1289 | if (wret) | |
1290 | ret = wret; | |
1291 | btrfs_block_release(root, path->nodes[0]); | |
1292 | path->nodes[0] = right_buffer; | |
1293 | path->slots[0] = 0; | |
1294 | path->slots[1] += 1; | |
1295 | return ret; | |
1296 | } | |
1297 | mid = slot; | |
1298 | double_split = 1; | |
1299 | } | |
1300 | } else { | |
1301 | if (leaf_space_used(l, 0, mid + 1) + space_needed > | |
1302 | BTRFS_LEAF_DATA_SIZE(root)) { | |
1303 | if (slot == 0) { | |
1304 | btrfs_cpu_key_to_disk(&disk_key, ins_key); | |
1305 | btrfs_set_header_nritems(&right->header, 0); | |
1306 | wret = insert_ptr(trans, root, path, | |
1307 | &disk_key, | |
7eccb903 | 1308 | bh_blocknr(right_buffer), |
d4dbff95 CM |
1309 | path->slots[1] - 1, 1); |
1310 | if (wret) | |
1311 | ret = wret; | |
1312 | btrfs_block_release(root, path->nodes[0]); | |
1313 | path->nodes[0] = right_buffer; | |
1314 | path->slots[0] = 0; | |
1315 | path->slots[1] -= 1; | |
a429e513 CM |
1316 | if (path->slots[1] == 0) { |
1317 | wret = fixup_low_keys(trans, root, | |
1318 | path, &disk_key, 1); | |
1319 | if (wret) | |
1320 | ret = wret; | |
1321 | } | |
d4dbff95 CM |
1322 | return ret; |
1323 | } | |
1324 | mid = slot; | |
1325 | double_split = 1; | |
1326 | } | |
1327 | } | |
1328 | btrfs_set_header_nritems(&right->header, nritems - mid); | |
123abc88 CM |
1329 | data_copy_size = btrfs_item_end(l->items + mid) - |
1330 | leaf_data_end(root, l); | |
d6025579 CM |
1331 | btrfs_memcpy(root, right, right->items, l->items + mid, |
1332 | (nritems - mid) * sizeof(struct btrfs_item)); | |
1333 | btrfs_memcpy(root, right, | |
1334 | btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - | |
1335 | data_copy_size, btrfs_leaf_data(l) + | |
1336 | leaf_data_end(root, l), data_copy_size); | |
123abc88 CM |
1337 | rt_data_off = BTRFS_LEAF_DATA_SIZE(root) - |
1338 | btrfs_item_end(l->items + mid); | |
74123bd7 | 1339 | |
0783fcfc | 1340 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
123abc88 | 1341 | u32 ioff = btrfs_item_offset(right->items + i); |
0783fcfc CM |
1342 | btrfs_set_item_offset(right->items + i, ioff + rt_data_off); |
1343 | } | |
74123bd7 | 1344 | |
7518a238 | 1345 | btrfs_set_header_nritems(&l->header, mid); |
aa5d6bed | 1346 | ret = 0; |
e089f05c | 1347 | wret = insert_ptr(trans, root, path, &right->items[0].key, |
7eccb903 | 1348 | bh_blocknr(right_buffer), path->slots[1] + 1, 1); |
aa5d6bed CM |
1349 | if (wret) |
1350 | ret = wret; | |
d6025579 CM |
1351 | btrfs_mark_buffer_dirty(right_buffer); |
1352 | btrfs_mark_buffer_dirty(l_buf); | |
eb60ceac | 1353 | BUG_ON(path->slots[0] != slot); |
be0e5c09 | 1354 | if (mid <= slot) { |
234b63a0 | 1355 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1356 | path->nodes[0] = right_buffer; |
be0e5c09 CM |
1357 | path->slots[0] -= mid; |
1358 | path->slots[1] += 1; | |
eb60ceac | 1359 | } else |
234b63a0 | 1360 | btrfs_block_release(root, right_buffer); |
eb60ceac | 1361 | BUG_ON(path->slots[0] < 0); |
d4dbff95 CM |
1362 | |
1363 | if (!double_split) | |
1364 | return ret; | |
1365 | right_buffer = btrfs_alloc_free_block(trans, root); | |
1366 | BUG_ON(!right_buffer); | |
1367 | right = btrfs_buffer_leaf(right_buffer); | |
1368 | memset(&right->header, 0, sizeof(right->header)); | |
7eccb903 | 1369 | btrfs_set_header_blocknr(&right->header, bh_blocknr(right_buffer)); |
d4dbff95 CM |
1370 | btrfs_set_header_generation(&right->header, trans->transid); |
1371 | btrfs_set_header_level(&right->header, 0); | |
3eb0314d CM |
1372 | memcpy(right->header.fsid, root->fs_info->disk_super->fsid, |
1373 | sizeof(right->header.fsid)); | |
d4dbff95 CM |
1374 | btrfs_cpu_key_to_disk(&disk_key, ins_key); |
1375 | btrfs_set_header_nritems(&right->header, 0); | |
1376 | wret = insert_ptr(trans, root, path, | |
1377 | &disk_key, | |
7eccb903 | 1378 | bh_blocknr(right_buffer), |
d4dbff95 CM |
1379 | path->slots[1], 1); |
1380 | if (wret) | |
1381 | ret = wret; | |
a429e513 CM |
1382 | if (path->slots[1] == 0) { |
1383 | wret = fixup_low_keys(trans, root, path, &disk_key, 1); | |
1384 | if (wret) | |
1385 | ret = wret; | |
1386 | } | |
d4dbff95 CM |
1387 | btrfs_block_release(root, path->nodes[0]); |
1388 | path->nodes[0] = right_buffer; | |
1389 | path->slots[0] = 0; | |
1390 | check_node(root, path, 1); | |
1391 | check_leaf(root, path, 0); | |
be0e5c09 CM |
1392 | return ret; |
1393 | } | |
1394 | ||
b18c6685 CM |
1395 | int btrfs_truncate_item(struct btrfs_trans_handle *trans, |
1396 | struct btrfs_root *root, | |
1397 | struct btrfs_path *path, | |
1398 | u32 new_size) | |
1399 | { | |
1400 | int ret = 0; | |
1401 | int slot; | |
1402 | int slot_orig; | |
1403 | struct btrfs_leaf *leaf; | |
1404 | struct buffer_head *leaf_buf; | |
1405 | u32 nritems; | |
1406 | unsigned int data_end; | |
1407 | unsigned int old_data_start; | |
1408 | unsigned int old_size; | |
1409 | unsigned int size_diff; | |
1410 | int i; | |
1411 | ||
1412 | slot_orig = path->slots[0]; | |
1413 | leaf_buf = path->nodes[0]; | |
1414 | leaf = btrfs_buffer_leaf(leaf_buf); | |
1415 | ||
1416 | nritems = btrfs_header_nritems(&leaf->header); | |
1417 | data_end = leaf_data_end(root, leaf); | |
1418 | ||
1419 | slot = path->slots[0]; | |
1420 | old_data_start = btrfs_item_offset(leaf->items + slot); | |
1421 | old_size = btrfs_item_size(leaf->items + slot); | |
1422 | BUG_ON(old_size <= new_size); | |
1423 | size_diff = old_size - new_size; | |
1424 | ||
1425 | BUG_ON(slot < 0); | |
1426 | BUG_ON(slot >= nritems); | |
1427 | ||
1428 | /* | |
1429 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1430 | */ | |
1431 | /* first correct the data pointers */ | |
1432 | for (i = slot; i < nritems; i++) { | |
1433 | u32 ioff = btrfs_item_offset(leaf->items + i); | |
1434 | btrfs_set_item_offset(leaf->items + i, | |
1435 | ioff + size_diff); | |
1436 | } | |
1437 | /* shift the data */ | |
b18c6685 CM |
1438 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + |
1439 | data_end + size_diff, btrfs_leaf_data(leaf) + | |
1440 | data_end, old_data_start + new_size - data_end); | |
1441 | btrfs_set_item_size(leaf->items + slot, new_size); | |
1442 | btrfs_mark_buffer_dirty(leaf_buf); | |
1443 | ||
1444 | ret = 0; | |
1445 | if (btrfs_leaf_free_space(root, leaf) < 0) | |
1446 | BUG(); | |
1447 | check_leaf(root, path, 0); | |
1448 | return ret; | |
1449 | } | |
1450 | ||
6567e837 CM |
1451 | int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1452 | *root, struct btrfs_path *path, u32 data_size) | |
1453 | { | |
1454 | int ret = 0; | |
1455 | int slot; | |
1456 | int slot_orig; | |
1457 | struct btrfs_leaf *leaf; | |
1458 | struct buffer_head *leaf_buf; | |
1459 | u32 nritems; | |
1460 | unsigned int data_end; | |
1461 | unsigned int old_data; | |
1462 | unsigned int old_size; | |
1463 | int i; | |
1464 | ||
1465 | slot_orig = path->slots[0]; | |
1466 | leaf_buf = path->nodes[0]; | |
1467 | leaf = btrfs_buffer_leaf(leaf_buf); | |
1468 | ||
1469 | nritems = btrfs_header_nritems(&leaf->header); | |
1470 | data_end = leaf_data_end(root, leaf); | |
1471 | ||
1472 | if (btrfs_leaf_free_space(root, leaf) < data_size) | |
1473 | BUG(); | |
1474 | slot = path->slots[0]; | |
1475 | old_data = btrfs_item_end(leaf->items + slot); | |
1476 | ||
1477 | BUG_ON(slot < 0); | |
1478 | BUG_ON(slot >= nritems); | |
1479 | ||
1480 | /* | |
1481 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1482 | */ | |
1483 | /* first correct the data pointers */ | |
1484 | for (i = slot; i < nritems; i++) { | |
1485 | u32 ioff = btrfs_item_offset(leaf->items + i); | |
1486 | btrfs_set_item_offset(leaf->items + i, | |
1487 | ioff - data_size); | |
1488 | } | |
1489 | /* shift the data */ | |
1490 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + | |
1491 | data_end - data_size, btrfs_leaf_data(leaf) + | |
1492 | data_end, old_data - data_end); | |
1493 | data_end = old_data; | |
1494 | old_size = btrfs_item_size(leaf->items + slot); | |
1495 | btrfs_set_item_size(leaf->items + slot, old_size + data_size); | |
1496 | btrfs_mark_buffer_dirty(leaf_buf); | |
1497 | ||
1498 | ret = 0; | |
1499 | if (btrfs_leaf_free_space(root, leaf) < 0) | |
1500 | BUG(); | |
1501 | check_leaf(root, path, 0); | |
1502 | return ret; | |
1503 | } | |
1504 | ||
74123bd7 CM |
1505 | /* |
1506 | * Given a key and some data, insert an item into the tree. | |
1507 | * This does all the path init required, making room in the tree if needed. | |
1508 | */ | |
e089f05c CM |
1509 | int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1510 | *root, struct btrfs_path *path, struct btrfs_key | |
1511 | *cpu_key, u32 data_size) | |
be0e5c09 | 1512 | { |
aa5d6bed | 1513 | int ret = 0; |
be0e5c09 | 1514 | int slot; |
eb60ceac | 1515 | int slot_orig; |
234b63a0 | 1516 | struct btrfs_leaf *leaf; |
e20d96d6 | 1517 | struct buffer_head *leaf_buf; |
7518a238 | 1518 | u32 nritems; |
be0e5c09 | 1519 | unsigned int data_end; |
e2fa7227 CM |
1520 | struct btrfs_disk_key disk_key; |
1521 | ||
1522 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); | |
be0e5c09 | 1523 | |
74123bd7 | 1524 | /* create a root if there isn't one */ |
5c680ed6 | 1525 | if (!root->node) |
cfaa7295 | 1526 | BUG(); |
e089f05c | 1527 | ret = btrfs_search_slot(trans, root, cpu_key, path, data_size, 1); |
eb60ceac | 1528 | if (ret == 0) { |
f0930a37 | 1529 | return -EEXIST; |
aa5d6bed | 1530 | } |
ed2ff2cb CM |
1531 | if (ret < 0) |
1532 | goto out; | |
be0e5c09 | 1533 | |
62e2749e CM |
1534 | slot_orig = path->slots[0]; |
1535 | leaf_buf = path->nodes[0]; | |
e20d96d6 | 1536 | leaf = btrfs_buffer_leaf(leaf_buf); |
74123bd7 | 1537 | |
7518a238 | 1538 | nritems = btrfs_header_nritems(&leaf->header); |
123abc88 | 1539 | data_end = leaf_data_end(root, leaf); |
eb60ceac | 1540 | |
123abc88 | 1541 | if (btrfs_leaf_free_space(root, leaf) < |
d4dbff95 | 1542 | sizeof(struct btrfs_item) + data_size) { |
be0e5c09 | 1543 | BUG(); |
d4dbff95 | 1544 | } |
62e2749e | 1545 | slot = path->slots[0]; |
eb60ceac | 1546 | BUG_ON(slot < 0); |
be0e5c09 CM |
1547 | if (slot != nritems) { |
1548 | int i; | |
0783fcfc | 1549 | unsigned int old_data = btrfs_item_end(leaf->items + slot); |
be0e5c09 CM |
1550 | |
1551 | /* | |
1552 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1553 | */ | |
1554 | /* first correct the data pointers */ | |
0783fcfc | 1555 | for (i = slot; i < nritems; i++) { |
123abc88 | 1556 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
1557 | btrfs_set_item_offset(leaf->items + i, |
1558 | ioff - data_size); | |
1559 | } | |
be0e5c09 CM |
1560 | |
1561 | /* shift the items */ | |
d6025579 CM |
1562 | btrfs_memmove(root, leaf, leaf->items + slot + 1, |
1563 | leaf->items + slot, | |
1564 | (nritems - slot) * sizeof(struct btrfs_item)); | |
be0e5c09 CM |
1565 | |
1566 | /* shift the data */ | |
d6025579 CM |
1567 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + |
1568 | data_end - data_size, btrfs_leaf_data(leaf) + | |
1569 | data_end, old_data - data_end); | |
be0e5c09 CM |
1570 | data_end = old_data; |
1571 | } | |
62e2749e | 1572 | /* setup the item for the new data */ |
d6025579 CM |
1573 | btrfs_memcpy(root, leaf, &leaf->items[slot].key, &disk_key, |
1574 | sizeof(struct btrfs_disk_key)); | |
0783fcfc CM |
1575 | btrfs_set_item_offset(leaf->items + slot, data_end - data_size); |
1576 | btrfs_set_item_size(leaf->items + slot, data_size); | |
7518a238 | 1577 | btrfs_set_header_nritems(&leaf->header, nritems + 1); |
d6025579 | 1578 | btrfs_mark_buffer_dirty(leaf_buf); |
aa5d6bed CM |
1579 | |
1580 | ret = 0; | |
8e19f2cd | 1581 | if (slot == 0) |
e089f05c | 1582 | ret = fixup_low_keys(trans, root, path, &disk_key, 1); |
aa5d6bed | 1583 | |
123abc88 | 1584 | if (btrfs_leaf_free_space(root, leaf) < 0) |
be0e5c09 | 1585 | BUG(); |
62e2749e | 1586 | check_leaf(root, path, 0); |
ed2ff2cb | 1587 | out: |
62e2749e CM |
1588 | return ret; |
1589 | } | |
1590 | ||
1591 | /* | |
1592 | * Given a key and some data, insert an item into the tree. | |
1593 | * This does all the path init required, making room in the tree if needed. | |
1594 | */ | |
e089f05c CM |
1595 | int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1596 | *root, struct btrfs_key *cpu_key, void *data, u32 | |
1597 | data_size) | |
62e2749e CM |
1598 | { |
1599 | int ret = 0; | |
2c90e5d6 | 1600 | struct btrfs_path *path; |
62e2749e CM |
1601 | u8 *ptr; |
1602 | ||
2c90e5d6 CM |
1603 | path = btrfs_alloc_path(); |
1604 | BUG_ON(!path); | |
1605 | btrfs_init_path(path); | |
1606 | ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size); | |
62e2749e | 1607 | if (!ret) { |
2c90e5d6 CM |
1608 | ptr = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), |
1609 | path->slots[0], u8); | |
1610 | btrfs_memcpy(root, path->nodes[0]->b_data, | |
d6025579 | 1611 | ptr, data, data_size); |
2c90e5d6 | 1612 | btrfs_mark_buffer_dirty(path->nodes[0]); |
62e2749e | 1613 | } |
2c90e5d6 CM |
1614 | btrfs_release_path(root, path); |
1615 | btrfs_free_path(path); | |
aa5d6bed | 1616 | return ret; |
be0e5c09 CM |
1617 | } |
1618 | ||
74123bd7 | 1619 | /* |
5de08d7d | 1620 | * delete the pointer from a given node. |
74123bd7 CM |
1621 | * |
1622 | * If the delete empties a node, the node is removed from the tree, | |
1623 | * continuing all the way the root if required. The root is converted into | |
1624 | * a leaf if all the nodes are emptied. | |
1625 | */ | |
e089f05c CM |
1626 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
1627 | struct btrfs_path *path, int level, int slot) | |
be0e5c09 | 1628 | { |
234b63a0 | 1629 | struct btrfs_node *node; |
e20d96d6 | 1630 | struct buffer_head *parent = path->nodes[level]; |
7518a238 | 1631 | u32 nritems; |
aa5d6bed | 1632 | int ret = 0; |
bb803951 | 1633 | int wret; |
be0e5c09 | 1634 | |
e20d96d6 | 1635 | node = btrfs_buffer_node(parent); |
7518a238 | 1636 | nritems = btrfs_header_nritems(&node->header); |
bb803951 | 1637 | if (slot != nritems -1) { |
d6025579 CM |
1638 | btrfs_memmove(root, node, node->ptrs + slot, |
1639 | node->ptrs + slot + 1, | |
1640 | sizeof(struct btrfs_key_ptr) * | |
1641 | (nritems - slot - 1)); | |
bb803951 | 1642 | } |
7518a238 CM |
1643 | nritems--; |
1644 | btrfs_set_header_nritems(&node->header, nritems); | |
1645 | if (nritems == 0 && parent == root->node) { | |
e20d96d6 CM |
1646 | struct btrfs_header *header = btrfs_buffer_header(root->node); |
1647 | BUG_ON(btrfs_header_level(header) != 1); | |
bb803951 | 1648 | /* just turn the root into a leaf and break */ |
e20d96d6 | 1649 | btrfs_set_header_level(header, 0); |
bb803951 | 1650 | } else if (slot == 0) { |
e089f05c | 1651 | wret = fixup_low_keys(trans, root, path, &node->ptrs[0].key, |
123abc88 | 1652 | level + 1); |
0f70abe2 CM |
1653 | if (wret) |
1654 | ret = wret; | |
be0e5c09 | 1655 | } |
d6025579 | 1656 | btrfs_mark_buffer_dirty(parent); |
aa5d6bed | 1657 | return ret; |
be0e5c09 CM |
1658 | } |
1659 | ||
74123bd7 CM |
1660 | /* |
1661 | * delete the item at the leaf level in path. If that empties | |
1662 | * the leaf, remove it from the tree | |
1663 | */ | |
e089f05c CM |
1664 | int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
1665 | struct btrfs_path *path) | |
be0e5c09 | 1666 | { |
be0e5c09 | 1667 | int slot; |
234b63a0 | 1668 | struct btrfs_leaf *leaf; |
e20d96d6 | 1669 | struct buffer_head *leaf_buf; |
be0e5c09 CM |
1670 | int doff; |
1671 | int dsize; | |
aa5d6bed CM |
1672 | int ret = 0; |
1673 | int wret; | |
7518a238 | 1674 | u32 nritems; |
be0e5c09 | 1675 | |
eb60ceac | 1676 | leaf_buf = path->nodes[0]; |
e20d96d6 | 1677 | leaf = btrfs_buffer_leaf(leaf_buf); |
4920c9ac | 1678 | slot = path->slots[0]; |
0783fcfc CM |
1679 | doff = btrfs_item_offset(leaf->items + slot); |
1680 | dsize = btrfs_item_size(leaf->items + slot); | |
7518a238 | 1681 | nritems = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 1682 | |
7518a238 | 1683 | if (slot != nritems - 1) { |
be0e5c09 | 1684 | int i; |
123abc88 | 1685 | int data_end = leaf_data_end(root, leaf); |
d6025579 CM |
1686 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + |
1687 | data_end + dsize, | |
1688 | btrfs_leaf_data(leaf) + data_end, | |
1689 | doff - data_end); | |
0783fcfc | 1690 | for (i = slot + 1; i < nritems; i++) { |
123abc88 | 1691 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
1692 | btrfs_set_item_offset(leaf->items + i, ioff + dsize); |
1693 | } | |
d6025579 CM |
1694 | btrfs_memmove(root, leaf, leaf->items + slot, |
1695 | leaf->items + slot + 1, | |
1696 | sizeof(struct btrfs_item) * | |
1697 | (nritems - slot - 1)); | |
be0e5c09 | 1698 | } |
7518a238 CM |
1699 | btrfs_set_header_nritems(&leaf->header, nritems - 1); |
1700 | nritems--; | |
74123bd7 | 1701 | /* delete the leaf if we've emptied it */ |
7518a238 | 1702 | if (nritems == 0) { |
eb60ceac | 1703 | if (leaf_buf == root->node) { |
7518a238 | 1704 | btrfs_set_header_level(&leaf->header, 0); |
9a8dd150 | 1705 | } else { |
e089f05c | 1706 | clean_tree_block(trans, root, leaf_buf); |
d6025579 | 1707 | wait_on_buffer(leaf_buf); |
e089f05c | 1708 | wret = del_ptr(trans, root, path, 1, path->slots[1]); |
aa5d6bed CM |
1709 | if (wret) |
1710 | ret = wret; | |
e089f05c | 1711 | wret = btrfs_free_extent(trans, root, |
7eccb903 | 1712 | bh_blocknr(leaf_buf), 1, 1); |
0f70abe2 CM |
1713 | if (wret) |
1714 | ret = wret; | |
9a8dd150 | 1715 | } |
be0e5c09 | 1716 | } else { |
7518a238 | 1717 | int used = leaf_space_used(leaf, 0, nritems); |
aa5d6bed | 1718 | if (slot == 0) { |
e089f05c CM |
1719 | wret = fixup_low_keys(trans, root, path, |
1720 | &leaf->items[0].key, 1); | |
aa5d6bed CM |
1721 | if (wret) |
1722 | ret = wret; | |
1723 | } | |
aa5d6bed | 1724 | |
74123bd7 | 1725 | /* delete the leaf if it is mostly empty */ |
123abc88 | 1726 | if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) { |
be0e5c09 CM |
1727 | /* push_leaf_left fixes the path. |
1728 | * make sure the path still points to our leaf | |
1729 | * for possible call to del_ptr below | |
1730 | */ | |
4920c9ac | 1731 | slot = path->slots[1]; |
e20d96d6 | 1732 | get_bh(leaf_buf); |
e089f05c | 1733 | wret = push_leaf_left(trans, root, path, 1); |
aa5d6bed CM |
1734 | if (wret < 0) |
1735 | ret = wret; | |
f0930a37 | 1736 | if (path->nodes[0] == leaf_buf && |
7518a238 | 1737 | btrfs_header_nritems(&leaf->header)) { |
e089f05c | 1738 | wret = push_leaf_right(trans, root, path, 1); |
aa5d6bed CM |
1739 | if (wret < 0) |
1740 | ret = wret; | |
1741 | } | |
7518a238 | 1742 | if (btrfs_header_nritems(&leaf->header) == 0) { |
7eccb903 | 1743 | u64 blocknr = bh_blocknr(leaf_buf); |
e089f05c | 1744 | clean_tree_block(trans, root, leaf_buf); |
d6025579 | 1745 | wait_on_buffer(leaf_buf); |
e089f05c | 1746 | wret = del_ptr(trans, root, path, 1, slot); |
aa5d6bed CM |
1747 | if (wret) |
1748 | ret = wret; | |
234b63a0 | 1749 | btrfs_block_release(root, leaf_buf); |
e089f05c CM |
1750 | wret = btrfs_free_extent(trans, root, blocknr, |
1751 | 1, 1); | |
0f70abe2 CM |
1752 | if (wret) |
1753 | ret = wret; | |
5de08d7d | 1754 | } else { |
d6025579 | 1755 | btrfs_mark_buffer_dirty(leaf_buf); |
234b63a0 | 1756 | btrfs_block_release(root, leaf_buf); |
be0e5c09 | 1757 | } |
d5719762 | 1758 | } else { |
d6025579 | 1759 | btrfs_mark_buffer_dirty(leaf_buf); |
be0e5c09 CM |
1760 | } |
1761 | } | |
aa5d6bed | 1762 | return ret; |
be0e5c09 CM |
1763 | } |
1764 | ||
97571fd0 CM |
1765 | /* |
1766 | * walk up the tree as far as required to find the next leaf. | |
0f70abe2 CM |
1767 | * returns 0 if it found something or 1 if there are no greater leaves. |
1768 | * returns < 0 on io errors. | |
97571fd0 | 1769 | */ |
234b63a0 | 1770 | int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) |
d97e63b6 CM |
1771 | { |
1772 | int slot; | |
1773 | int level = 1; | |
1774 | u64 blocknr; | |
e20d96d6 CM |
1775 | struct buffer_head *c; |
1776 | struct btrfs_node *c_node; | |
1777 | struct buffer_head *next = NULL; | |
d97e63b6 | 1778 | |
234b63a0 | 1779 | while(level < BTRFS_MAX_LEVEL) { |
d97e63b6 | 1780 | if (!path->nodes[level]) |
0f70abe2 | 1781 | return 1; |
d97e63b6 CM |
1782 | slot = path->slots[level] + 1; |
1783 | c = path->nodes[level]; | |
e20d96d6 CM |
1784 | c_node = btrfs_buffer_node(c); |
1785 | if (slot >= btrfs_header_nritems(&c_node->header)) { | |
d97e63b6 CM |
1786 | level++; |
1787 | continue; | |
1788 | } | |
e20d96d6 | 1789 | blocknr = btrfs_node_blockptr(c_node, slot); |
cfaa7295 | 1790 | if (next) |
234b63a0 | 1791 | btrfs_block_release(root, next); |
d97e63b6 CM |
1792 | next = read_tree_block(root, blocknr); |
1793 | break; | |
1794 | } | |
1795 | path->slots[level] = slot; | |
1796 | while(1) { | |
1797 | level--; | |
1798 | c = path->nodes[level]; | |
234b63a0 | 1799 | btrfs_block_release(root, c); |
d97e63b6 CM |
1800 | path->nodes[level] = next; |
1801 | path->slots[level] = 0; | |
1802 | if (!level) | |
1803 | break; | |
1d4f8a0c | 1804 | next = read_tree_block(root, |
e20d96d6 | 1805 | btrfs_node_blockptr(btrfs_buffer_node(next), 0)); |
d97e63b6 CM |
1806 | } |
1807 | return 0; | |
1808 | } |