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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/hfs/brec.c
4 *
5 * Copyright (C) 2001
6 * Brad Boyer (flar@allandria.com)
7 * (C) 2003 Ardis Technologies <roman@ardistech.com>
8 *
9 * Handle individual btree records
10 */
11
12#include "btree.h"
13
14static struct hfs_bnode *hfs_bnode_split(struct hfs_find_data *fd);
15static int hfs_brec_update_parent(struct hfs_find_data *fd);
16static int hfs_btree_inc_height(struct hfs_btree *tree);
17
18/* Get the length and offset of the given record in the given node */
19u16 hfs_brec_lenoff(struct hfs_bnode *node, u16 rec, u16 *off)
20{
21 __be16 retval[2];
22 u16 dataoff;
23
24 dataoff = node->tree->node_size - (rec + 2) * 2;
25 hfs_bnode_read(node, retval, dataoff, 4);
26 *off = be16_to_cpu(retval[1]);
27 return be16_to_cpu(retval[0]) - *off;
28}
29
30/* Get the length of the key from a keyed record */
31u16 hfs_brec_keylen(struct hfs_bnode *node, u16 rec)
32{
33 u16 retval, recoff;
34
35 if (node->type != HFS_NODE_INDEX && node->type != HFS_NODE_LEAF)
36 return 0;
37
38 if ((node->type == HFS_NODE_INDEX) &&
39 !(node->tree->attributes & HFS_TREE_VARIDXKEYS)) {
40 if (node->tree->attributes & HFS_TREE_BIGKEYS)
41 retval = node->tree->max_key_len + 2;
42 else
43 retval = node->tree->max_key_len + 1;
44 } else {
45 recoff = hfs_bnode_read_u16(node, node->tree->node_size - (rec + 1) * 2);
46 if (!recoff)
47 return 0;
48 if (node->tree->attributes & HFS_TREE_BIGKEYS) {
49 retval = hfs_bnode_read_u16(node, recoff) + 2;
50 if (retval > node->tree->max_key_len + 2) {
51 pr_err("keylen %d too large\n", retval);
52 retval = 0;
53 }
54 } else {
55 retval = (hfs_bnode_read_u8(node, recoff) | 1) + 1;
56 if (retval > node->tree->max_key_len + 1) {
57 pr_err("keylen %d too large\n", retval);
58 retval = 0;
59 }
60 }
61 }
62 return retval;
63}
64
65int hfs_brec_insert(struct hfs_find_data *fd, void *entry, int entry_len)
66{
67 struct hfs_btree *tree;
68 struct hfs_bnode *node, *new_node;
69 int size, key_len, rec;
70 int data_off, end_off;
71 int idx_rec_off, data_rec_off, end_rec_off;
72 __be32 cnid;
73
74 tree = fd->tree;
75 if (!fd->bnode) {
76 if (!tree->root)
77 hfs_btree_inc_height(tree);
78 fd->bnode = hfs_bnode_find(tree, tree->leaf_head);
79 if (IS_ERR(fd->bnode))
80 return PTR_ERR(fd->bnode);
81 fd->record = -1;
82 }
83 new_node = NULL;
84 key_len = (fd->search_key->key_len | 1) + 1;
85again:
86 /* new record idx and complete record size */
87 rec = fd->record + 1;
88 size = key_len + entry_len;
89
90 node = fd->bnode;
91 hfs_bnode_dump(node);
92 /* get last offset */
93 end_rec_off = tree->node_size - (node->num_recs + 1) * 2;
94 end_off = hfs_bnode_read_u16(node, end_rec_off);
95 end_rec_off -= 2;
96 hfs_dbg(BNODE_MOD, "insert_rec: %d, %d, %d, %d\n",
97 rec, size, end_off, end_rec_off);
98 if (size > end_rec_off - end_off) {
99 if (new_node)
100 panic("not enough room!\n");
101 new_node = hfs_bnode_split(fd);
102 if (IS_ERR(new_node))
103 return PTR_ERR(new_node);
104 goto again;
105 }
106 if (node->type == HFS_NODE_LEAF) {
107 tree->leaf_count++;
108 mark_inode_dirty(tree->inode);
109 }
110 node->num_recs++;
111 /* write new last offset */
112 hfs_bnode_write_u16(node, offsetof(struct hfs_bnode_desc, num_recs), node->num_recs);
113 hfs_bnode_write_u16(node, end_rec_off, end_off + size);
114 data_off = end_off;
115 data_rec_off = end_rec_off + 2;
116 idx_rec_off = tree->node_size - (rec + 1) * 2;
117 if (idx_rec_off == data_rec_off)
118 goto skip;
119 /* move all following entries */
120 do {
121 data_off = hfs_bnode_read_u16(node, data_rec_off + 2);
122 hfs_bnode_write_u16(node, data_rec_off, data_off + size);
123 data_rec_off += 2;
124 } while (data_rec_off < idx_rec_off);
125
126 /* move data away */
127 hfs_bnode_move(node, data_off + size, data_off,
128 end_off - data_off);
129
130skip:
131 hfs_bnode_write(node, fd->search_key, data_off, key_len);
132 hfs_bnode_write(node, entry, data_off + key_len, entry_len);
133 hfs_bnode_dump(node);
134
135 /*
136 * update parent key if we inserted a key
137 * at the start of the node and it is not the new node
138 */
139 if (!rec && new_node != node) {
140 hfs_bnode_read_key(node, fd->search_key, data_off + size);
141 hfs_brec_update_parent(fd);
142 }
143
144 if (new_node) {
145 hfs_bnode_put(fd->bnode);
146 if (!new_node->parent) {
147 hfs_btree_inc_height(tree);
148 new_node->parent = tree->root;
149 }
150 fd->bnode = hfs_bnode_find(tree, new_node->parent);
151
152 /* create index data entry */
153 cnid = cpu_to_be32(new_node->this);
154 entry = &cnid;
155 entry_len = sizeof(cnid);
156
157 /* get index key */
158 hfs_bnode_read_key(new_node, fd->search_key, 14);
159 __hfs_brec_find(fd->bnode, fd);
160
161 hfs_bnode_put(new_node);
162 new_node = NULL;
163
164 if (tree->attributes & HFS_TREE_VARIDXKEYS)
165 key_len = fd->search_key->key_len + 1;
166 else {
167 fd->search_key->key_len = tree->max_key_len;
168 key_len = tree->max_key_len + 1;
169 }
170 goto again;
171 }
172
173 return 0;
174}
175
176int hfs_brec_remove(struct hfs_find_data *fd)
177{
178 struct hfs_btree *tree;
179 struct hfs_bnode *node, *parent;
180 int end_off, rec_off, data_off, size;
181
182 tree = fd->tree;
183 node = fd->bnode;
184again:
185 rec_off = tree->node_size - (fd->record + 2) * 2;
186 end_off = tree->node_size - (node->num_recs + 1) * 2;
187
188 if (node->type == HFS_NODE_LEAF) {
189 tree->leaf_count--;
190 mark_inode_dirty(tree->inode);
191 }
192 hfs_bnode_dump(node);
193 hfs_dbg(BNODE_MOD, "remove_rec: %d, %d\n",
194 fd->record, fd->keylength + fd->entrylength);
195 if (!--node->num_recs) {
196 hfs_bnode_unlink(node);
197 if (!node->parent)
198 return 0;
199 parent = hfs_bnode_find(tree, node->parent);
200 if (IS_ERR(parent))
201 return PTR_ERR(parent);
202 hfs_bnode_put(node);
203 node = fd->bnode = parent;
204
205 __hfs_brec_find(node, fd);
206 goto again;
207 }
208 hfs_bnode_write_u16(node, offsetof(struct hfs_bnode_desc, num_recs), node->num_recs);
209
210 if (rec_off == end_off)
211 goto skip;
212 size = fd->keylength + fd->entrylength;
213
214 do {
215 data_off = hfs_bnode_read_u16(node, rec_off);
216 hfs_bnode_write_u16(node, rec_off + 2, data_off - size);
217 rec_off -= 2;
218 } while (rec_off >= end_off);
219
220 /* fill hole */
221 hfs_bnode_move(node, fd->keyoffset, fd->keyoffset + size,
222 data_off - fd->keyoffset - size);
223skip:
224 hfs_bnode_dump(node);
225 if (!fd->record)
226 hfs_brec_update_parent(fd);
227 return 0;
228}
229
230static struct hfs_bnode *hfs_bnode_split(struct hfs_find_data *fd)
231{
232 struct hfs_btree *tree;
233 struct hfs_bnode *node, *new_node, *next_node;
234 struct hfs_bnode_desc node_desc;
235 int num_recs, new_rec_off, new_off, old_rec_off;
236 int data_start, data_end, size;
237
238 tree = fd->tree;
239 node = fd->bnode;
240 new_node = hfs_bmap_alloc(tree);
241 if (IS_ERR(new_node))
242 return new_node;
243 hfs_bnode_get(node);
244 hfs_dbg(BNODE_MOD, "split_nodes: %d - %d - %d\n",
245 node->this, new_node->this, node->next);
246 new_node->next = node->next;
247 new_node->prev = node->this;
248 new_node->parent = node->parent;
249 new_node->type = node->type;
250 new_node->height = node->height;
251
252 if (node->next)
253 next_node = hfs_bnode_find(tree, node->next);
254 else
255 next_node = NULL;
256
257 if (IS_ERR(next_node)) {
258 hfs_bnode_put(node);
259 hfs_bnode_put(new_node);
260 return next_node;
261 }
262
263 size = tree->node_size / 2 - node->num_recs * 2 - 14;
264 old_rec_off = tree->node_size - 4;
265 num_recs = 1;
266 for (;;) {
267 data_start = hfs_bnode_read_u16(node, old_rec_off);
268 if (data_start > size)
269 break;
270 old_rec_off -= 2;
271 if (++num_recs < node->num_recs)
272 continue;
273 /* panic? */
274 hfs_bnode_put(node);
275 hfs_bnode_put(new_node);
276 if (next_node)
277 hfs_bnode_put(next_node);
278 return ERR_PTR(-ENOSPC);
279 }
280
281 if (fd->record + 1 < num_recs) {
282 /* new record is in the lower half,
283 * so leave some more space there
284 */
285 old_rec_off += 2;
286 num_recs--;
287 data_start = hfs_bnode_read_u16(node, old_rec_off);
288 } else {
289 hfs_bnode_put(node);
290 hfs_bnode_get(new_node);
291 fd->bnode = new_node;
292 fd->record -= num_recs;
293 fd->keyoffset -= data_start - 14;
294 fd->entryoffset -= data_start - 14;
295 }
296 new_node->num_recs = node->num_recs - num_recs;
297 node->num_recs = num_recs;
298
299 new_rec_off = tree->node_size - 2;
300 new_off = 14;
301 size = data_start - new_off;
302 num_recs = new_node->num_recs;
303 data_end = data_start;
304 while (num_recs) {
305 hfs_bnode_write_u16(new_node, new_rec_off, new_off);
306 old_rec_off -= 2;
307 new_rec_off -= 2;
308 data_end = hfs_bnode_read_u16(node, old_rec_off);
309 new_off = data_end - size;
310 num_recs--;
311 }
312 hfs_bnode_write_u16(new_node, new_rec_off, new_off);
313 hfs_bnode_copy(new_node, 14, node, data_start, data_end - data_start);
314
315 /* update new bnode header */
316 node_desc.next = cpu_to_be32(new_node->next);
317 node_desc.prev = cpu_to_be32(new_node->prev);
318 node_desc.type = new_node->type;
319 node_desc.height = new_node->height;
320 node_desc.num_recs = cpu_to_be16(new_node->num_recs);
321 node_desc.reserved = 0;
322 hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));
323
324 /* update previous bnode header */
325 node->next = new_node->this;
326 hfs_bnode_read(node, &node_desc, 0, sizeof(node_desc));
327 node_desc.next = cpu_to_be32(node->next);
328 node_desc.num_recs = cpu_to_be16(node->num_recs);
329 hfs_bnode_write(node, &node_desc, 0, sizeof(node_desc));
330
331 /* update next bnode header */
332 if (next_node) {
333 next_node->prev = new_node->this;
334 hfs_bnode_read(next_node, &node_desc, 0, sizeof(node_desc));
335 node_desc.prev = cpu_to_be32(next_node->prev);
336 hfs_bnode_write(next_node, &node_desc, 0, sizeof(node_desc));
337 hfs_bnode_put(next_node);
338 } else if (node->this == tree->leaf_tail) {
339 /* if there is no next node, this might be the new tail */
340 tree->leaf_tail = new_node->this;
341 mark_inode_dirty(tree->inode);
342 }
343
344 hfs_bnode_dump(node);
345 hfs_bnode_dump(new_node);
346 hfs_bnode_put(node);
347
348 return new_node;
349}
350
351static int hfs_brec_update_parent(struct hfs_find_data *fd)
352{
353 struct hfs_btree *tree;
354 struct hfs_bnode *node, *new_node, *parent;
355 int newkeylen, diff;
356 int rec, rec_off, end_rec_off;
357 int start_off, end_off;
358
359 tree = fd->tree;
360 node = fd->bnode;
361 new_node = NULL;
362 if (!node->parent)
363 return 0;
364
365again:
366 parent = hfs_bnode_find(tree, node->parent);
367 if (IS_ERR(parent))
368 return PTR_ERR(parent);
369 __hfs_brec_find(parent, fd);
370 if (fd->record < 0)
371 return -ENOENT;
372 hfs_bnode_dump(parent);
373 rec = fd->record;
374
375 /* size difference between old and new key */
376 if (tree->attributes & HFS_TREE_VARIDXKEYS)
377 newkeylen = (hfs_bnode_read_u8(node, 14) | 1) + 1;
378 else
379 fd->keylength = newkeylen = tree->max_key_len + 1;
380 hfs_dbg(BNODE_MOD, "update_rec: %d, %d, %d\n",
381 rec, fd->keylength, newkeylen);
382
383 rec_off = tree->node_size - (rec + 2) * 2;
384 end_rec_off = tree->node_size - (parent->num_recs + 1) * 2;
385 diff = newkeylen - fd->keylength;
386 if (!diff)
387 goto skip;
388 if (diff > 0) {
389 end_off = hfs_bnode_read_u16(parent, end_rec_off);
390 if (end_rec_off - end_off < diff) {
391
392 printk(KERN_DEBUG "splitting index node...\n");
393 fd->bnode = parent;
394 new_node = hfs_bnode_split(fd);
395 if (IS_ERR(new_node))
396 return PTR_ERR(new_node);
397 parent = fd->bnode;
398 rec = fd->record;
399 rec_off = tree->node_size - (rec + 2) * 2;
400 end_rec_off = tree->node_size - (parent->num_recs + 1) * 2;
401 }
402 }
403
404 end_off = start_off = hfs_bnode_read_u16(parent, rec_off);
405 hfs_bnode_write_u16(parent, rec_off, start_off + diff);
406 start_off -= 4; /* move previous cnid too */
407
408 while (rec_off > end_rec_off) {
409 rec_off -= 2;
410 end_off = hfs_bnode_read_u16(parent, rec_off);
411 hfs_bnode_write_u16(parent, rec_off, end_off + diff);
412 }
413 hfs_bnode_move(parent, start_off + diff, start_off,
414 end_off - start_off);
415skip:
416 hfs_bnode_copy(parent, fd->keyoffset, node, 14, newkeylen);
417 if (!(tree->attributes & HFS_TREE_VARIDXKEYS))
418 hfs_bnode_write_u8(parent, fd->keyoffset, newkeylen - 1);
419 hfs_bnode_dump(parent);
420
421 hfs_bnode_put(node);
422 node = parent;
423
424 if (new_node) {
425 __be32 cnid;
426
427 fd->bnode = hfs_bnode_find(tree, new_node->parent);
428 /* create index key and entry */
429 hfs_bnode_read_key(new_node, fd->search_key, 14);
430 cnid = cpu_to_be32(new_node->this);
431
432 __hfs_brec_find(fd->bnode, fd);
433 hfs_brec_insert(fd, &cnid, sizeof(cnid));
434 hfs_bnode_put(fd->bnode);
435 hfs_bnode_put(new_node);
436
437 if (!rec) {
438 if (new_node == node)
439 goto out;
440 /* restore search_key */
441 hfs_bnode_read_key(node, fd->search_key, 14);
442 }
443 }
444
445 if (!rec && node->parent)
446 goto again;
447out:
448 fd->bnode = node;
449 return 0;
450}
451
452static int hfs_btree_inc_height(struct hfs_btree *tree)
453{
454 struct hfs_bnode *node, *new_node;
455 struct hfs_bnode_desc node_desc;
456 int key_size, rec;
457 __be32 cnid;
458
459 node = NULL;
460 if (tree->root) {
461 node = hfs_bnode_find(tree, tree->root);
462 if (IS_ERR(node))
463 return PTR_ERR(node);
464 }
465 new_node = hfs_bmap_alloc(tree);
466 if (IS_ERR(new_node)) {
467 hfs_bnode_put(node);
468 return PTR_ERR(new_node);
469 }
470
471 tree->root = new_node->this;
472 if (!tree->depth) {
473 tree->leaf_head = tree->leaf_tail = new_node->this;
474 new_node->type = HFS_NODE_LEAF;
475 new_node->num_recs = 0;
476 } else {
477 new_node->type = HFS_NODE_INDEX;
478 new_node->num_recs = 1;
479 }
480 new_node->parent = 0;
481 new_node->next = 0;
482 new_node->prev = 0;
483 new_node->height = ++tree->depth;
484
485 node_desc.next = cpu_to_be32(new_node->next);
486 node_desc.prev = cpu_to_be32(new_node->prev);
487 node_desc.type = new_node->type;
488 node_desc.height = new_node->height;
489 node_desc.num_recs = cpu_to_be16(new_node->num_recs);
490 node_desc.reserved = 0;
491 hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));
492
493 rec = tree->node_size - 2;
494 hfs_bnode_write_u16(new_node, rec, 14);
495
496 if (node) {
497 /* insert old root idx into new root */
498 node->parent = tree->root;
499 if (node->type == HFS_NODE_LEAF ||
500 tree->attributes & HFS_TREE_VARIDXKEYS)
501 key_size = hfs_bnode_read_u8(node, 14) + 1;
502 else
503 key_size = tree->max_key_len + 1;
504 hfs_bnode_copy(new_node, 14, node, 14, key_size);
505
506 if (!(tree->attributes & HFS_TREE_VARIDXKEYS)) {
507 key_size = tree->max_key_len + 1;
508 hfs_bnode_write_u8(new_node, 14, tree->max_key_len);
509 }
510 key_size = (key_size + 1) & -2;
511 cnid = cpu_to_be32(node->this);
512 hfs_bnode_write(new_node, &cnid, 14 + key_size, 4);
513
514 rec -= 2;
515 hfs_bnode_write_u16(new_node, rec, 14 + key_size + 4);
516
517 hfs_bnode_put(node);
518 }
519 hfs_bnode_put(new_node);
520 mark_inode_dirty(tree->inode);
521
522 return 0;
523}
1/*
2 * linux/fs/hfs/brec.c
3 *
4 * Copyright (C) 2001
5 * Brad Boyer (flar@allandria.com)
6 * (C) 2003 Ardis Technologies <roman@ardistech.com>
7 *
8 * Handle individual btree records
9 */
10
11#include "btree.h"
12
13static struct hfs_bnode *hfs_bnode_split(struct hfs_find_data *fd);
14static int hfs_brec_update_parent(struct hfs_find_data *fd);
15static int hfs_btree_inc_height(struct hfs_btree *tree);
16
17/* Get the length and offset of the given record in the given node */
18u16 hfs_brec_lenoff(struct hfs_bnode *node, u16 rec, u16 *off)
19{
20 __be16 retval[2];
21 u16 dataoff;
22
23 dataoff = node->tree->node_size - (rec + 2) * 2;
24 hfs_bnode_read(node, retval, dataoff, 4);
25 *off = be16_to_cpu(retval[1]);
26 return be16_to_cpu(retval[0]) - *off;
27}
28
29/* Get the length of the key from a keyed record */
30u16 hfs_brec_keylen(struct hfs_bnode *node, u16 rec)
31{
32 u16 retval, recoff;
33
34 if (node->type != HFS_NODE_INDEX && node->type != HFS_NODE_LEAF)
35 return 0;
36
37 if ((node->type == HFS_NODE_INDEX) &&
38 !(node->tree->attributes & HFS_TREE_VARIDXKEYS)) {
39 if (node->tree->attributes & HFS_TREE_BIGKEYS)
40 retval = node->tree->max_key_len + 2;
41 else
42 retval = node->tree->max_key_len + 1;
43 } else {
44 recoff = hfs_bnode_read_u16(node, node->tree->node_size - (rec + 1) * 2);
45 if (!recoff)
46 return 0;
47 if (node->tree->attributes & HFS_TREE_BIGKEYS) {
48 retval = hfs_bnode_read_u16(node, recoff) + 2;
49 if (retval > node->tree->max_key_len + 2) {
50 pr_err("keylen %d too large\n", retval);
51 retval = 0;
52 }
53 } else {
54 retval = (hfs_bnode_read_u8(node, recoff) | 1) + 1;
55 if (retval > node->tree->max_key_len + 1) {
56 pr_err("keylen %d too large\n", retval);
57 retval = 0;
58 }
59 }
60 }
61 return retval;
62}
63
64int hfs_brec_insert(struct hfs_find_data *fd, void *entry, int entry_len)
65{
66 struct hfs_btree *tree;
67 struct hfs_bnode *node, *new_node;
68 int size, key_len, rec;
69 int data_off, end_off;
70 int idx_rec_off, data_rec_off, end_rec_off;
71 __be32 cnid;
72
73 tree = fd->tree;
74 if (!fd->bnode) {
75 if (!tree->root)
76 hfs_btree_inc_height(tree);
77 fd->bnode = hfs_bnode_find(tree, tree->leaf_head);
78 if (IS_ERR(fd->bnode))
79 return PTR_ERR(fd->bnode);
80 fd->record = -1;
81 }
82 new_node = NULL;
83 key_len = (fd->search_key->key_len | 1) + 1;
84again:
85 /* new record idx and complete record size */
86 rec = fd->record + 1;
87 size = key_len + entry_len;
88
89 node = fd->bnode;
90 hfs_bnode_dump(node);
91 /* get last offset */
92 end_rec_off = tree->node_size - (node->num_recs + 1) * 2;
93 end_off = hfs_bnode_read_u16(node, end_rec_off);
94 end_rec_off -= 2;
95 hfs_dbg(BNODE_MOD, "insert_rec: %d, %d, %d, %d\n",
96 rec, size, end_off, end_rec_off);
97 if (size > end_rec_off - end_off) {
98 if (new_node)
99 panic("not enough room!\n");
100 new_node = hfs_bnode_split(fd);
101 if (IS_ERR(new_node))
102 return PTR_ERR(new_node);
103 goto again;
104 }
105 if (node->type == HFS_NODE_LEAF) {
106 tree->leaf_count++;
107 mark_inode_dirty(tree->inode);
108 }
109 node->num_recs++;
110 /* write new last offset */
111 hfs_bnode_write_u16(node, offsetof(struct hfs_bnode_desc, num_recs), node->num_recs);
112 hfs_bnode_write_u16(node, end_rec_off, end_off + size);
113 data_off = end_off;
114 data_rec_off = end_rec_off + 2;
115 idx_rec_off = tree->node_size - (rec + 1) * 2;
116 if (idx_rec_off == data_rec_off)
117 goto skip;
118 /* move all following entries */
119 do {
120 data_off = hfs_bnode_read_u16(node, data_rec_off + 2);
121 hfs_bnode_write_u16(node, data_rec_off, data_off + size);
122 data_rec_off += 2;
123 } while (data_rec_off < idx_rec_off);
124
125 /* move data away */
126 hfs_bnode_move(node, data_off + size, data_off,
127 end_off - data_off);
128
129skip:
130 hfs_bnode_write(node, fd->search_key, data_off, key_len);
131 hfs_bnode_write(node, entry, data_off + key_len, entry_len);
132 hfs_bnode_dump(node);
133
134 if (new_node) {
135 /* update parent key if we inserted a key
136 * at the start of the first node
137 */
138 if (!rec && new_node != node)
139 hfs_brec_update_parent(fd);
140
141 hfs_bnode_put(fd->bnode);
142 if (!new_node->parent) {
143 hfs_btree_inc_height(tree);
144 new_node->parent = tree->root;
145 }
146 fd->bnode = hfs_bnode_find(tree, new_node->parent);
147
148 /* create index data entry */
149 cnid = cpu_to_be32(new_node->this);
150 entry = &cnid;
151 entry_len = sizeof(cnid);
152
153 /* get index key */
154 hfs_bnode_read_key(new_node, fd->search_key, 14);
155 __hfs_brec_find(fd->bnode, fd);
156
157 hfs_bnode_put(new_node);
158 new_node = NULL;
159
160 if (tree->attributes & HFS_TREE_VARIDXKEYS)
161 key_len = fd->search_key->key_len + 1;
162 else {
163 fd->search_key->key_len = tree->max_key_len;
164 key_len = tree->max_key_len + 1;
165 }
166 goto again;
167 }
168
169 if (!rec)
170 hfs_brec_update_parent(fd);
171
172 return 0;
173}
174
175int hfs_brec_remove(struct hfs_find_data *fd)
176{
177 struct hfs_btree *tree;
178 struct hfs_bnode *node, *parent;
179 int end_off, rec_off, data_off, size;
180
181 tree = fd->tree;
182 node = fd->bnode;
183again:
184 rec_off = tree->node_size - (fd->record + 2) * 2;
185 end_off = tree->node_size - (node->num_recs + 1) * 2;
186
187 if (node->type == HFS_NODE_LEAF) {
188 tree->leaf_count--;
189 mark_inode_dirty(tree->inode);
190 }
191 hfs_bnode_dump(node);
192 hfs_dbg(BNODE_MOD, "remove_rec: %d, %d\n",
193 fd->record, fd->keylength + fd->entrylength);
194 if (!--node->num_recs) {
195 hfs_bnode_unlink(node);
196 if (!node->parent)
197 return 0;
198 parent = hfs_bnode_find(tree, node->parent);
199 if (IS_ERR(parent))
200 return PTR_ERR(parent);
201 hfs_bnode_put(node);
202 node = fd->bnode = parent;
203
204 __hfs_brec_find(node, fd);
205 goto again;
206 }
207 hfs_bnode_write_u16(node, offsetof(struct hfs_bnode_desc, num_recs), node->num_recs);
208
209 if (rec_off == end_off)
210 goto skip;
211 size = fd->keylength + fd->entrylength;
212
213 do {
214 data_off = hfs_bnode_read_u16(node, rec_off);
215 hfs_bnode_write_u16(node, rec_off + 2, data_off - size);
216 rec_off -= 2;
217 } while (rec_off >= end_off);
218
219 /* fill hole */
220 hfs_bnode_move(node, fd->keyoffset, fd->keyoffset + size,
221 data_off - fd->keyoffset - size);
222skip:
223 hfs_bnode_dump(node);
224 if (!fd->record)
225 hfs_brec_update_parent(fd);
226 return 0;
227}
228
229static struct hfs_bnode *hfs_bnode_split(struct hfs_find_data *fd)
230{
231 struct hfs_btree *tree;
232 struct hfs_bnode *node, *new_node, *next_node;
233 struct hfs_bnode_desc node_desc;
234 int num_recs, new_rec_off, new_off, old_rec_off;
235 int data_start, data_end, size;
236
237 tree = fd->tree;
238 node = fd->bnode;
239 new_node = hfs_bmap_alloc(tree);
240 if (IS_ERR(new_node))
241 return new_node;
242 hfs_bnode_get(node);
243 hfs_dbg(BNODE_MOD, "split_nodes: %d - %d - %d\n",
244 node->this, new_node->this, node->next);
245 new_node->next = node->next;
246 new_node->prev = node->this;
247 new_node->parent = node->parent;
248 new_node->type = node->type;
249 new_node->height = node->height;
250
251 if (node->next)
252 next_node = hfs_bnode_find(tree, node->next);
253 else
254 next_node = NULL;
255
256 if (IS_ERR(next_node)) {
257 hfs_bnode_put(node);
258 hfs_bnode_put(new_node);
259 return next_node;
260 }
261
262 size = tree->node_size / 2 - node->num_recs * 2 - 14;
263 old_rec_off = tree->node_size - 4;
264 num_recs = 1;
265 for (;;) {
266 data_start = hfs_bnode_read_u16(node, old_rec_off);
267 if (data_start > size)
268 break;
269 old_rec_off -= 2;
270 if (++num_recs < node->num_recs)
271 continue;
272 /* panic? */
273 hfs_bnode_put(node);
274 hfs_bnode_put(new_node);
275 if (next_node)
276 hfs_bnode_put(next_node);
277 return ERR_PTR(-ENOSPC);
278 }
279
280 if (fd->record + 1 < num_recs) {
281 /* new record is in the lower half,
282 * so leave some more space there
283 */
284 old_rec_off += 2;
285 num_recs--;
286 data_start = hfs_bnode_read_u16(node, old_rec_off);
287 } else {
288 hfs_bnode_put(node);
289 hfs_bnode_get(new_node);
290 fd->bnode = new_node;
291 fd->record -= num_recs;
292 fd->keyoffset -= data_start - 14;
293 fd->entryoffset -= data_start - 14;
294 }
295 new_node->num_recs = node->num_recs - num_recs;
296 node->num_recs = num_recs;
297
298 new_rec_off = tree->node_size - 2;
299 new_off = 14;
300 size = data_start - new_off;
301 num_recs = new_node->num_recs;
302 data_end = data_start;
303 while (num_recs) {
304 hfs_bnode_write_u16(new_node, new_rec_off, new_off);
305 old_rec_off -= 2;
306 new_rec_off -= 2;
307 data_end = hfs_bnode_read_u16(node, old_rec_off);
308 new_off = data_end - size;
309 num_recs--;
310 }
311 hfs_bnode_write_u16(new_node, new_rec_off, new_off);
312 hfs_bnode_copy(new_node, 14, node, data_start, data_end - data_start);
313
314 /* update new bnode header */
315 node_desc.next = cpu_to_be32(new_node->next);
316 node_desc.prev = cpu_to_be32(new_node->prev);
317 node_desc.type = new_node->type;
318 node_desc.height = new_node->height;
319 node_desc.num_recs = cpu_to_be16(new_node->num_recs);
320 node_desc.reserved = 0;
321 hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));
322
323 /* update previous bnode header */
324 node->next = new_node->this;
325 hfs_bnode_read(node, &node_desc, 0, sizeof(node_desc));
326 node_desc.next = cpu_to_be32(node->next);
327 node_desc.num_recs = cpu_to_be16(node->num_recs);
328 hfs_bnode_write(node, &node_desc, 0, sizeof(node_desc));
329
330 /* update next bnode header */
331 if (next_node) {
332 next_node->prev = new_node->this;
333 hfs_bnode_read(next_node, &node_desc, 0, sizeof(node_desc));
334 node_desc.prev = cpu_to_be32(next_node->prev);
335 hfs_bnode_write(next_node, &node_desc, 0, sizeof(node_desc));
336 hfs_bnode_put(next_node);
337 } else if (node->this == tree->leaf_tail) {
338 /* if there is no next node, this might be the new tail */
339 tree->leaf_tail = new_node->this;
340 mark_inode_dirty(tree->inode);
341 }
342
343 hfs_bnode_dump(node);
344 hfs_bnode_dump(new_node);
345 hfs_bnode_put(node);
346
347 return new_node;
348}
349
350static int hfs_brec_update_parent(struct hfs_find_data *fd)
351{
352 struct hfs_btree *tree;
353 struct hfs_bnode *node, *new_node, *parent;
354 int newkeylen, diff;
355 int rec, rec_off, end_rec_off;
356 int start_off, end_off;
357
358 tree = fd->tree;
359 node = fd->bnode;
360 new_node = NULL;
361 if (!node->parent)
362 return 0;
363
364again:
365 parent = hfs_bnode_find(tree, node->parent);
366 if (IS_ERR(parent))
367 return PTR_ERR(parent);
368 __hfs_brec_find(parent, fd);
369 hfs_bnode_dump(parent);
370 rec = fd->record;
371
372 /* size difference between old and new key */
373 if (tree->attributes & HFS_TREE_VARIDXKEYS)
374 newkeylen = (hfs_bnode_read_u8(node, 14) | 1) + 1;
375 else
376 fd->keylength = newkeylen = tree->max_key_len + 1;
377 hfs_dbg(BNODE_MOD, "update_rec: %d, %d, %d\n",
378 rec, fd->keylength, newkeylen);
379
380 rec_off = tree->node_size - (rec + 2) * 2;
381 end_rec_off = tree->node_size - (parent->num_recs + 1) * 2;
382 diff = newkeylen - fd->keylength;
383 if (!diff)
384 goto skip;
385 if (diff > 0) {
386 end_off = hfs_bnode_read_u16(parent, end_rec_off);
387 if (end_rec_off - end_off < diff) {
388
389 printk(KERN_DEBUG "splitting index node...\n");
390 fd->bnode = parent;
391 new_node = hfs_bnode_split(fd);
392 if (IS_ERR(new_node))
393 return PTR_ERR(new_node);
394 parent = fd->bnode;
395 rec = fd->record;
396 rec_off = tree->node_size - (rec + 2) * 2;
397 end_rec_off = tree->node_size - (parent->num_recs + 1) * 2;
398 }
399 }
400
401 end_off = start_off = hfs_bnode_read_u16(parent, rec_off);
402 hfs_bnode_write_u16(parent, rec_off, start_off + diff);
403 start_off -= 4; /* move previous cnid too */
404
405 while (rec_off > end_rec_off) {
406 rec_off -= 2;
407 end_off = hfs_bnode_read_u16(parent, rec_off);
408 hfs_bnode_write_u16(parent, rec_off, end_off + diff);
409 }
410 hfs_bnode_move(parent, start_off + diff, start_off,
411 end_off - start_off);
412skip:
413 hfs_bnode_copy(parent, fd->keyoffset, node, 14, newkeylen);
414 if (!(tree->attributes & HFS_TREE_VARIDXKEYS))
415 hfs_bnode_write_u8(parent, fd->keyoffset, newkeylen - 1);
416 hfs_bnode_dump(parent);
417
418 hfs_bnode_put(node);
419 node = parent;
420
421 if (new_node) {
422 __be32 cnid;
423
424 fd->bnode = hfs_bnode_find(tree, new_node->parent);
425 /* create index key and entry */
426 hfs_bnode_read_key(new_node, fd->search_key, 14);
427 cnid = cpu_to_be32(new_node->this);
428
429 __hfs_brec_find(fd->bnode, fd);
430 hfs_brec_insert(fd, &cnid, sizeof(cnid));
431 hfs_bnode_put(fd->bnode);
432 hfs_bnode_put(new_node);
433
434 if (!rec) {
435 if (new_node == node)
436 goto out;
437 /* restore search_key */
438 hfs_bnode_read_key(node, fd->search_key, 14);
439 }
440 }
441
442 if (!rec && node->parent)
443 goto again;
444out:
445 fd->bnode = node;
446 return 0;
447}
448
449static int hfs_btree_inc_height(struct hfs_btree *tree)
450{
451 struct hfs_bnode *node, *new_node;
452 struct hfs_bnode_desc node_desc;
453 int key_size, rec;
454 __be32 cnid;
455
456 node = NULL;
457 if (tree->root) {
458 node = hfs_bnode_find(tree, tree->root);
459 if (IS_ERR(node))
460 return PTR_ERR(node);
461 }
462 new_node = hfs_bmap_alloc(tree);
463 if (IS_ERR(new_node)) {
464 hfs_bnode_put(node);
465 return PTR_ERR(new_node);
466 }
467
468 tree->root = new_node->this;
469 if (!tree->depth) {
470 tree->leaf_head = tree->leaf_tail = new_node->this;
471 new_node->type = HFS_NODE_LEAF;
472 new_node->num_recs = 0;
473 } else {
474 new_node->type = HFS_NODE_INDEX;
475 new_node->num_recs = 1;
476 }
477 new_node->parent = 0;
478 new_node->next = 0;
479 new_node->prev = 0;
480 new_node->height = ++tree->depth;
481
482 node_desc.next = cpu_to_be32(new_node->next);
483 node_desc.prev = cpu_to_be32(new_node->prev);
484 node_desc.type = new_node->type;
485 node_desc.height = new_node->height;
486 node_desc.num_recs = cpu_to_be16(new_node->num_recs);
487 node_desc.reserved = 0;
488 hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));
489
490 rec = tree->node_size - 2;
491 hfs_bnode_write_u16(new_node, rec, 14);
492
493 if (node) {
494 /* insert old root idx into new root */
495 node->parent = tree->root;
496 if (node->type == HFS_NODE_LEAF ||
497 tree->attributes & HFS_TREE_VARIDXKEYS)
498 key_size = hfs_bnode_read_u8(node, 14) + 1;
499 else
500 key_size = tree->max_key_len + 1;
501 hfs_bnode_copy(new_node, 14, node, 14, key_size);
502
503 if (!(tree->attributes & HFS_TREE_VARIDXKEYS)) {
504 key_size = tree->max_key_len + 1;
505 hfs_bnode_write_u8(new_node, 14, tree->max_key_len);
506 }
507 key_size = (key_size + 1) & -2;
508 cnid = cpu_to_be32(node->this);
509 hfs_bnode_write(new_node, &cnid, 14 + key_size, 4);
510
511 rec -= 2;
512 hfs_bnode_write_u16(new_node, rec, 14 + key_size + 4);
513
514 hfs_bnode_put(node);
515 }
516 hfs_bnode_put(new_node);
517 mark_inode_dirty(tree->inode);
518
519 return 0;
520}