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1/*
2 * linux/fs/hfsplus/bnode.c
3 *
4 * Copyright (C) 2001
5 * Brad Boyer (flar@allandria.com)
6 * (C) 2003 Ardis Technologies <roman@ardistech.com>
7 *
8 * Handle basic btree node operations
9 */
10
11#include <linux/string.h>
12#include <linux/slab.h>
13#include <linux/pagemap.h>
14#include <linux/fs.h>
15#include <linux/swap.h>
16
17#include "hfsplus_fs.h"
18#include "hfsplus_raw.h"
19
20/* Copy a specified range of bytes from the raw data of a node */
21void hfs_bnode_read(struct hfs_bnode *node, void *buf, int off, int len)
22{
23 struct page **pagep;
24 int l;
25
26 off += node->page_offset;
27 pagep = node->page + (off >> PAGE_SHIFT);
28 off &= ~PAGE_MASK;
29
30 l = min_t(int, len, PAGE_SIZE - off);
31 memcpy(buf, kmap(*pagep) + off, l);
32 kunmap(*pagep);
33
34 while ((len -= l) != 0) {
35 buf += l;
36 l = min_t(int, len, PAGE_SIZE);
37 memcpy(buf, kmap(*++pagep), l);
38 kunmap(*pagep);
39 }
40}
41
42u16 hfs_bnode_read_u16(struct hfs_bnode *node, int off)
43{
44 __be16 data;
45 /* TODO: optimize later... */
46 hfs_bnode_read(node, &data, off, 2);
47 return be16_to_cpu(data);
48}
49
50u8 hfs_bnode_read_u8(struct hfs_bnode *node, int off)
51{
52 u8 data;
53 /* TODO: optimize later... */
54 hfs_bnode_read(node, &data, off, 1);
55 return data;
56}
57
58void hfs_bnode_read_key(struct hfs_bnode *node, void *key, int off)
59{
60 struct hfs_btree *tree;
61 int key_len;
62
63 tree = node->tree;
64 if (node->type == HFS_NODE_LEAF ||
65 tree->attributes & HFS_TREE_VARIDXKEYS ||
66 node->tree->cnid == HFSPLUS_ATTR_CNID)
67 key_len = hfs_bnode_read_u16(node, off) + 2;
68 else
69 key_len = tree->max_key_len + 2;
70
71 hfs_bnode_read(node, key, off, key_len);
72}
73
74void hfs_bnode_write(struct hfs_bnode *node, void *buf, int off, int len)
75{
76 struct page **pagep;
77 int l;
78
79 off += node->page_offset;
80 pagep = node->page + (off >> PAGE_SHIFT);
81 off &= ~PAGE_MASK;
82
83 l = min_t(int, len, PAGE_SIZE - off);
84 memcpy(kmap(*pagep) + off, buf, l);
85 set_page_dirty(*pagep);
86 kunmap(*pagep);
87
88 while ((len -= l) != 0) {
89 buf += l;
90 l = min_t(int, len, PAGE_SIZE);
91 memcpy(kmap(*++pagep), buf, l);
92 set_page_dirty(*pagep);
93 kunmap(*pagep);
94 }
95}
96
97void hfs_bnode_write_u16(struct hfs_bnode *node, int off, u16 data)
98{
99 __be16 v = cpu_to_be16(data);
100 /* TODO: optimize later... */
101 hfs_bnode_write(node, &v, off, 2);
102}
103
104void hfs_bnode_clear(struct hfs_bnode *node, int off, int len)
105{
106 struct page **pagep;
107 int l;
108
109 off += node->page_offset;
110 pagep = node->page + (off >> PAGE_SHIFT);
111 off &= ~PAGE_MASK;
112
113 l = min_t(int, len, PAGE_SIZE - off);
114 memset(kmap(*pagep) + off, 0, l);
115 set_page_dirty(*pagep);
116 kunmap(*pagep);
117
118 while ((len -= l) != 0) {
119 l = min_t(int, len, PAGE_SIZE);
120 memset(kmap(*++pagep), 0, l);
121 set_page_dirty(*pagep);
122 kunmap(*pagep);
123 }
124}
125
126void hfs_bnode_copy(struct hfs_bnode *dst_node, int dst,
127 struct hfs_bnode *src_node, int src, int len)
128{
129 struct hfs_btree *tree;
130 struct page **src_page, **dst_page;
131 int l;
132
133 hfs_dbg(BNODE_MOD, "copybytes: %u,%u,%u\n", dst, src, len);
134 if (!len)
135 return;
136 tree = src_node->tree;
137 src += src_node->page_offset;
138 dst += dst_node->page_offset;
139 src_page = src_node->page + (src >> PAGE_SHIFT);
140 src &= ~PAGE_MASK;
141 dst_page = dst_node->page + (dst >> PAGE_SHIFT);
142 dst &= ~PAGE_MASK;
143
144 if (src == dst) {
145 l = min_t(int, len, PAGE_SIZE - src);
146 memcpy(kmap(*dst_page) + src, kmap(*src_page) + src, l);
147 kunmap(*src_page);
148 set_page_dirty(*dst_page);
149 kunmap(*dst_page);
150
151 while ((len -= l) != 0) {
152 l = min_t(int, len, PAGE_SIZE);
153 memcpy(kmap(*++dst_page), kmap(*++src_page), l);
154 kunmap(*src_page);
155 set_page_dirty(*dst_page);
156 kunmap(*dst_page);
157 }
158 } else {
159 void *src_ptr, *dst_ptr;
160
161 do {
162 src_ptr = kmap(*src_page) + src;
163 dst_ptr = kmap(*dst_page) + dst;
164 if (PAGE_SIZE - src < PAGE_SIZE - dst) {
165 l = PAGE_SIZE - src;
166 src = 0;
167 dst += l;
168 } else {
169 l = PAGE_SIZE - dst;
170 src += l;
171 dst = 0;
172 }
173 l = min(len, l);
174 memcpy(dst_ptr, src_ptr, l);
175 kunmap(*src_page);
176 set_page_dirty(*dst_page);
177 kunmap(*dst_page);
178 if (!dst)
179 dst_page++;
180 else
181 src_page++;
182 } while ((len -= l));
183 }
184}
185
186void hfs_bnode_move(struct hfs_bnode *node, int dst, int src, int len)
187{
188 struct page **src_page, **dst_page;
189 int l;
190
191 hfs_dbg(BNODE_MOD, "movebytes: %u,%u,%u\n", dst, src, len);
192 if (!len)
193 return;
194 src += node->page_offset;
195 dst += node->page_offset;
196 if (dst > src) {
197 src += len - 1;
198 src_page = node->page + (src >> PAGE_SHIFT);
199 src = (src & ~PAGE_MASK) + 1;
200 dst += len - 1;
201 dst_page = node->page + (dst >> PAGE_SHIFT);
202 dst = (dst & ~PAGE_MASK) + 1;
203
204 if (src == dst) {
205 while (src < len) {
206 memmove(kmap(*dst_page), kmap(*src_page), src);
207 kunmap(*src_page);
208 set_page_dirty(*dst_page);
209 kunmap(*dst_page);
210 len -= src;
211 src = PAGE_SIZE;
212 src_page--;
213 dst_page--;
214 }
215 src -= len;
216 memmove(kmap(*dst_page) + src,
217 kmap(*src_page) + src, len);
218 kunmap(*src_page);
219 set_page_dirty(*dst_page);
220 kunmap(*dst_page);
221 } else {
222 void *src_ptr, *dst_ptr;
223
224 do {
225 src_ptr = kmap(*src_page) + src;
226 dst_ptr = kmap(*dst_page) + dst;
227 if (src < dst) {
228 l = src;
229 src = PAGE_SIZE;
230 dst -= l;
231 } else {
232 l = dst;
233 src -= l;
234 dst = PAGE_SIZE;
235 }
236 l = min(len, l);
237 memmove(dst_ptr - l, src_ptr - l, l);
238 kunmap(*src_page);
239 set_page_dirty(*dst_page);
240 kunmap(*dst_page);
241 if (dst == PAGE_SIZE)
242 dst_page--;
243 else
244 src_page--;
245 } while ((len -= l));
246 }
247 } else {
248 src_page = node->page + (src >> PAGE_SHIFT);
249 src &= ~PAGE_MASK;
250 dst_page = node->page + (dst >> PAGE_SHIFT);
251 dst &= ~PAGE_MASK;
252
253 if (src == dst) {
254 l = min_t(int, len, PAGE_SIZE - src);
255 memmove(kmap(*dst_page) + src,
256 kmap(*src_page) + src, l);
257 kunmap(*src_page);
258 set_page_dirty(*dst_page);
259 kunmap(*dst_page);
260
261 while ((len -= l) != 0) {
262 l = min_t(int, len, PAGE_SIZE);
263 memmove(kmap(*++dst_page),
264 kmap(*++src_page), l);
265 kunmap(*src_page);
266 set_page_dirty(*dst_page);
267 kunmap(*dst_page);
268 }
269 } else {
270 void *src_ptr, *dst_ptr;
271
272 do {
273 src_ptr = kmap(*src_page) + src;
274 dst_ptr = kmap(*dst_page) + dst;
275 if (PAGE_SIZE - src <
276 PAGE_SIZE - dst) {
277 l = PAGE_SIZE - src;
278 src = 0;
279 dst += l;
280 } else {
281 l = PAGE_SIZE - dst;
282 src += l;
283 dst = 0;
284 }
285 l = min(len, l);
286 memmove(dst_ptr, src_ptr, l);
287 kunmap(*src_page);
288 set_page_dirty(*dst_page);
289 kunmap(*dst_page);
290 if (!dst)
291 dst_page++;
292 else
293 src_page++;
294 } while ((len -= l));
295 }
296 }
297}
298
299void hfs_bnode_dump(struct hfs_bnode *node)
300{
301 struct hfs_bnode_desc desc;
302 __be32 cnid;
303 int i, off, key_off;
304
305 hfs_dbg(BNODE_MOD, "bnode: %d\n", node->this);
306 hfs_bnode_read(node, &desc, 0, sizeof(desc));
307 hfs_dbg(BNODE_MOD, "%d, %d, %d, %d, %d\n",
308 be32_to_cpu(desc.next), be32_to_cpu(desc.prev),
309 desc.type, desc.height, be16_to_cpu(desc.num_recs));
310
311 off = node->tree->node_size - 2;
312 for (i = be16_to_cpu(desc.num_recs); i >= 0; off -= 2, i--) {
313 key_off = hfs_bnode_read_u16(node, off);
314 hfs_dbg(BNODE_MOD, " %d", key_off);
315 if (i && node->type == HFS_NODE_INDEX) {
316 int tmp;
317
318 if (node->tree->attributes & HFS_TREE_VARIDXKEYS ||
319 node->tree->cnid == HFSPLUS_ATTR_CNID)
320 tmp = hfs_bnode_read_u16(node, key_off) + 2;
321 else
322 tmp = node->tree->max_key_len + 2;
323 hfs_dbg_cont(BNODE_MOD, " (%d", tmp);
324 hfs_bnode_read(node, &cnid, key_off + tmp, 4);
325 hfs_dbg_cont(BNODE_MOD, ",%d)", be32_to_cpu(cnid));
326 } else if (i && node->type == HFS_NODE_LEAF) {
327 int tmp;
328
329 tmp = hfs_bnode_read_u16(node, key_off);
330 hfs_dbg_cont(BNODE_MOD, " (%d)", tmp);
331 }
332 }
333 hfs_dbg_cont(BNODE_MOD, "\n");
334}
335
336void hfs_bnode_unlink(struct hfs_bnode *node)
337{
338 struct hfs_btree *tree;
339 struct hfs_bnode *tmp;
340 __be32 cnid;
341
342 tree = node->tree;
343 if (node->prev) {
344 tmp = hfs_bnode_find(tree, node->prev);
345 if (IS_ERR(tmp))
346 return;
347 tmp->next = node->next;
348 cnid = cpu_to_be32(tmp->next);
349 hfs_bnode_write(tmp, &cnid,
350 offsetof(struct hfs_bnode_desc, next), 4);
351 hfs_bnode_put(tmp);
352 } else if (node->type == HFS_NODE_LEAF)
353 tree->leaf_head = node->next;
354
355 if (node->next) {
356 tmp = hfs_bnode_find(tree, node->next);
357 if (IS_ERR(tmp))
358 return;
359 tmp->prev = node->prev;
360 cnid = cpu_to_be32(tmp->prev);
361 hfs_bnode_write(tmp, &cnid,
362 offsetof(struct hfs_bnode_desc, prev), 4);
363 hfs_bnode_put(tmp);
364 } else if (node->type == HFS_NODE_LEAF)
365 tree->leaf_tail = node->prev;
366
367 /* move down? */
368 if (!node->prev && !node->next)
369 hfs_dbg(BNODE_MOD, "hfs_btree_del_level\n");
370 if (!node->parent) {
371 tree->root = 0;
372 tree->depth = 0;
373 }
374 set_bit(HFS_BNODE_DELETED, &node->flags);
375}
376
377static inline int hfs_bnode_hash(u32 num)
378{
379 num = (num >> 16) + num;
380 num += num >> 8;
381 return num & (NODE_HASH_SIZE - 1);
382}
383
384struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *tree, u32 cnid)
385{
386 struct hfs_bnode *node;
387
388 if (cnid >= tree->node_count) {
389 pr_err("request for non-existent node %d in B*Tree\n",
390 cnid);
391 return NULL;
392 }
393
394 for (node = tree->node_hash[hfs_bnode_hash(cnid)];
395 node; node = node->next_hash)
396 if (node->this == cnid)
397 return node;
398 return NULL;
399}
400
401static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid)
402{
403 struct super_block *sb;
404 struct hfs_bnode *node, *node2;
405 struct address_space *mapping;
406 struct page *page;
407 int size, block, i, hash;
408 loff_t off;
409
410 if (cnid >= tree->node_count) {
411 pr_err("request for non-existent node %d in B*Tree\n",
412 cnid);
413 return NULL;
414 }
415
416 sb = tree->inode->i_sb;
417 size = sizeof(struct hfs_bnode) + tree->pages_per_bnode *
418 sizeof(struct page *);
419 node = kzalloc(size, GFP_KERNEL);
420 if (!node)
421 return NULL;
422 node->tree = tree;
423 node->this = cnid;
424 set_bit(HFS_BNODE_NEW, &node->flags);
425 atomic_set(&node->refcnt, 1);
426 hfs_dbg(BNODE_REFS, "new_node(%d:%d): 1\n",
427 node->tree->cnid, node->this);
428 init_waitqueue_head(&node->lock_wq);
429 spin_lock(&tree->hash_lock);
430 node2 = hfs_bnode_findhash(tree, cnid);
431 if (!node2) {
432 hash = hfs_bnode_hash(cnid);
433 node->next_hash = tree->node_hash[hash];
434 tree->node_hash[hash] = node;
435 tree->node_hash_cnt++;
436 } else {
437 spin_unlock(&tree->hash_lock);
438 kfree(node);
439 wait_event(node2->lock_wq,
440 !test_bit(HFS_BNODE_NEW, &node2->flags));
441 return node2;
442 }
443 spin_unlock(&tree->hash_lock);
444
445 mapping = tree->inode->i_mapping;
446 off = (loff_t)cnid << tree->node_size_shift;
447 block = off >> PAGE_SHIFT;
448 node->page_offset = off & ~PAGE_MASK;
449 for (i = 0; i < tree->pages_per_bnode; block++, i++) {
450 page = read_mapping_page(mapping, block, NULL);
451 if (IS_ERR(page))
452 goto fail;
453 if (PageError(page)) {
454 put_page(page);
455 goto fail;
456 }
457 node->page[i] = page;
458 }
459
460 return node;
461fail:
462 set_bit(HFS_BNODE_ERROR, &node->flags);
463 return node;
464}
465
466void hfs_bnode_unhash(struct hfs_bnode *node)
467{
468 struct hfs_bnode **p;
469
470 hfs_dbg(BNODE_REFS, "remove_node(%d:%d): %d\n",
471 node->tree->cnid, node->this, atomic_read(&node->refcnt));
472 for (p = &node->tree->node_hash[hfs_bnode_hash(node->this)];
473 *p && *p != node; p = &(*p)->next_hash)
474 ;
475 BUG_ON(!*p);
476 *p = node->next_hash;
477 node->tree->node_hash_cnt--;
478}
479
480/* Load a particular node out of a tree */
481struct hfs_bnode *hfs_bnode_find(struct hfs_btree *tree, u32 num)
482{
483 struct hfs_bnode *node;
484 struct hfs_bnode_desc *desc;
485 int i, rec_off, off, next_off;
486 int entry_size, key_size;
487
488 spin_lock(&tree->hash_lock);
489 node = hfs_bnode_findhash(tree, num);
490 if (node) {
491 hfs_bnode_get(node);
492 spin_unlock(&tree->hash_lock);
493 wait_event(node->lock_wq,
494 !test_bit(HFS_BNODE_NEW, &node->flags));
495 if (test_bit(HFS_BNODE_ERROR, &node->flags))
496 goto node_error;
497 return node;
498 }
499 spin_unlock(&tree->hash_lock);
500 node = __hfs_bnode_create(tree, num);
501 if (!node)
502 return ERR_PTR(-ENOMEM);
503 if (test_bit(HFS_BNODE_ERROR, &node->flags))
504 goto node_error;
505 if (!test_bit(HFS_BNODE_NEW, &node->flags))
506 return node;
507
508 desc = (struct hfs_bnode_desc *)(kmap(node->page[0]) +
509 node->page_offset);
510 node->prev = be32_to_cpu(desc->prev);
511 node->next = be32_to_cpu(desc->next);
512 node->num_recs = be16_to_cpu(desc->num_recs);
513 node->type = desc->type;
514 node->height = desc->height;
515 kunmap(node->page[0]);
516
517 switch (node->type) {
518 case HFS_NODE_HEADER:
519 case HFS_NODE_MAP:
520 if (node->height != 0)
521 goto node_error;
522 break;
523 case HFS_NODE_LEAF:
524 if (node->height != 1)
525 goto node_error;
526 break;
527 case HFS_NODE_INDEX:
528 if (node->height <= 1 || node->height > tree->depth)
529 goto node_error;
530 break;
531 default:
532 goto node_error;
533 }
534
535 rec_off = tree->node_size - 2;
536 off = hfs_bnode_read_u16(node, rec_off);
537 if (off != sizeof(struct hfs_bnode_desc))
538 goto node_error;
539 for (i = 1; i <= node->num_recs; off = next_off, i++) {
540 rec_off -= 2;
541 next_off = hfs_bnode_read_u16(node, rec_off);
542 if (next_off <= off ||
543 next_off > tree->node_size ||
544 next_off & 1)
545 goto node_error;
546 entry_size = next_off - off;
547 if (node->type != HFS_NODE_INDEX &&
548 node->type != HFS_NODE_LEAF)
549 continue;
550 key_size = hfs_bnode_read_u16(node, off) + 2;
551 if (key_size >= entry_size || key_size & 1)
552 goto node_error;
553 }
554 clear_bit(HFS_BNODE_NEW, &node->flags);
555 wake_up(&node->lock_wq);
556 return node;
557
558node_error:
559 set_bit(HFS_BNODE_ERROR, &node->flags);
560 clear_bit(HFS_BNODE_NEW, &node->flags);
561 wake_up(&node->lock_wq);
562 hfs_bnode_put(node);
563 return ERR_PTR(-EIO);
564}
565
566void hfs_bnode_free(struct hfs_bnode *node)
567{
568 int i;
569
570 for (i = 0; i < node->tree->pages_per_bnode; i++)
571 if (node->page[i])
572 put_page(node->page[i]);
573 kfree(node);
574}
575
576struct hfs_bnode *hfs_bnode_create(struct hfs_btree *tree, u32 num)
577{
578 struct hfs_bnode *node;
579 struct page **pagep;
580 int i;
581
582 spin_lock(&tree->hash_lock);
583 node = hfs_bnode_findhash(tree, num);
584 spin_unlock(&tree->hash_lock);
585 if (node) {
586 pr_crit("new node %u already hashed?\n", num);
587 WARN_ON(1);
588 return node;
589 }
590 node = __hfs_bnode_create(tree, num);
591 if (!node)
592 return ERR_PTR(-ENOMEM);
593 if (test_bit(HFS_BNODE_ERROR, &node->flags)) {
594 hfs_bnode_put(node);
595 return ERR_PTR(-EIO);
596 }
597
598 pagep = node->page;
599 memset(kmap(*pagep) + node->page_offset, 0,
600 min_t(int, PAGE_SIZE, tree->node_size));
601 set_page_dirty(*pagep);
602 kunmap(*pagep);
603 for (i = 1; i < tree->pages_per_bnode; i++) {
604 memset(kmap(*++pagep), 0, PAGE_SIZE);
605 set_page_dirty(*pagep);
606 kunmap(*pagep);
607 }
608 clear_bit(HFS_BNODE_NEW, &node->flags);
609 wake_up(&node->lock_wq);
610
611 return node;
612}
613
614void hfs_bnode_get(struct hfs_bnode *node)
615{
616 if (node) {
617 atomic_inc(&node->refcnt);
618 hfs_dbg(BNODE_REFS, "get_node(%d:%d): %d\n",
619 node->tree->cnid, node->this,
620 atomic_read(&node->refcnt));
621 }
622}
623
624/* Dispose of resources used by a node */
625void hfs_bnode_put(struct hfs_bnode *node)
626{
627 if (node) {
628 struct hfs_btree *tree = node->tree;
629 int i;
630
631 hfs_dbg(BNODE_REFS, "put_node(%d:%d): %d\n",
632 node->tree->cnid, node->this,
633 atomic_read(&node->refcnt));
634 BUG_ON(!atomic_read(&node->refcnt));
635 if (!atomic_dec_and_lock(&node->refcnt, &tree->hash_lock))
636 return;
637 for (i = 0; i < tree->pages_per_bnode; i++) {
638 if (!node->page[i])
639 continue;
640 mark_page_accessed(node->page[i]);
641 }
642
643 if (test_bit(HFS_BNODE_DELETED, &node->flags)) {
644 hfs_bnode_unhash(node);
645 spin_unlock(&tree->hash_lock);
646 if (hfs_bnode_need_zeroout(tree))
647 hfs_bnode_clear(node, 0, tree->node_size);
648 hfs_bmap_free(node);
649 hfs_bnode_free(node);
650 return;
651 }
652 spin_unlock(&tree->hash_lock);
653 }
654}
655
656/*
657 * Unused nodes have to be zeroed if this is the catalog tree and
658 * a corresponding flag in the volume header is set.
659 */
660bool hfs_bnode_need_zeroout(struct hfs_btree *tree)
661{
662 struct super_block *sb = tree->inode->i_sb;
663 struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
664 const u32 volume_attr = be32_to_cpu(sbi->s_vhdr->attributes);
665
666 return tree->cnid == HFSPLUS_CAT_CNID &&
667 volume_attr & HFSPLUS_VOL_UNUSED_NODE_FIX;
668}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/hfsplus/bnode.c
4 *
5 * Copyright (C) 2001
6 * Brad Boyer (flar@allandria.com)
7 * (C) 2003 Ardis Technologies <roman@ardistech.com>
8 *
9 * Handle basic btree node operations
10 */
11
12#include <linux/string.h>
13#include <linux/slab.h>
14#include <linux/pagemap.h>
15#include <linux/fs.h>
16#include <linux/swap.h>
17
18#include "hfsplus_fs.h"
19#include "hfsplus_raw.h"
20
21/* Copy a specified range of bytes from the raw data of a node */
22void hfs_bnode_read(struct hfs_bnode *node, void *buf, int off, int len)
23{
24 struct page **pagep;
25 int l;
26
27 off += node->page_offset;
28 pagep = node->page + (off >> PAGE_SHIFT);
29 off &= ~PAGE_MASK;
30
31 l = min_t(int, len, PAGE_SIZE - off);
32 memcpy_from_page(buf, *pagep, off, l);
33
34 while ((len -= l) != 0) {
35 buf += l;
36 l = min_t(int, len, PAGE_SIZE);
37 memcpy_from_page(buf, *++pagep, 0, l);
38 }
39}
40
41u16 hfs_bnode_read_u16(struct hfs_bnode *node, int off)
42{
43 __be16 data;
44 /* TODO: optimize later... */
45 hfs_bnode_read(node, &data, off, 2);
46 return be16_to_cpu(data);
47}
48
49u8 hfs_bnode_read_u8(struct hfs_bnode *node, int off)
50{
51 u8 data;
52 /* TODO: optimize later... */
53 hfs_bnode_read(node, &data, off, 1);
54 return data;
55}
56
57void hfs_bnode_read_key(struct hfs_bnode *node, void *key, int off)
58{
59 struct hfs_btree *tree;
60 int key_len;
61
62 tree = node->tree;
63 if (node->type == HFS_NODE_LEAF ||
64 tree->attributes & HFS_TREE_VARIDXKEYS ||
65 node->tree->cnid == HFSPLUS_ATTR_CNID)
66 key_len = hfs_bnode_read_u16(node, off) + 2;
67 else
68 key_len = tree->max_key_len + 2;
69
70 hfs_bnode_read(node, key, off, key_len);
71}
72
73void hfs_bnode_write(struct hfs_bnode *node, void *buf, int off, int len)
74{
75 struct page **pagep;
76 int l;
77
78 off += node->page_offset;
79 pagep = node->page + (off >> PAGE_SHIFT);
80 off &= ~PAGE_MASK;
81
82 l = min_t(int, len, PAGE_SIZE - off);
83 memcpy_to_page(*pagep, off, buf, l);
84 set_page_dirty(*pagep);
85
86 while ((len -= l) != 0) {
87 buf += l;
88 l = min_t(int, len, PAGE_SIZE);
89 memcpy_to_page(*++pagep, 0, buf, l);
90 set_page_dirty(*pagep);
91 }
92}
93
94void hfs_bnode_write_u16(struct hfs_bnode *node, int off, u16 data)
95{
96 __be16 v = cpu_to_be16(data);
97 /* TODO: optimize later... */
98 hfs_bnode_write(node, &v, off, 2);
99}
100
101void hfs_bnode_clear(struct hfs_bnode *node, int off, int len)
102{
103 struct page **pagep;
104 int l;
105
106 off += node->page_offset;
107 pagep = node->page + (off >> PAGE_SHIFT);
108 off &= ~PAGE_MASK;
109
110 l = min_t(int, len, PAGE_SIZE - off);
111 memzero_page(*pagep, off, l);
112 set_page_dirty(*pagep);
113
114 while ((len -= l) != 0) {
115 l = min_t(int, len, PAGE_SIZE);
116 memzero_page(*++pagep, 0, l);
117 set_page_dirty(*pagep);
118 }
119}
120
121void hfs_bnode_copy(struct hfs_bnode *dst_node, int dst,
122 struct hfs_bnode *src_node, int src, int len)
123{
124 struct page **src_page, **dst_page;
125 int l;
126
127 hfs_dbg(BNODE_MOD, "copybytes: %u,%u,%u\n", dst, src, len);
128 if (!len)
129 return;
130 src += src_node->page_offset;
131 dst += dst_node->page_offset;
132 src_page = src_node->page + (src >> PAGE_SHIFT);
133 src &= ~PAGE_MASK;
134 dst_page = dst_node->page + (dst >> PAGE_SHIFT);
135 dst &= ~PAGE_MASK;
136
137 if (src == dst) {
138 l = min_t(int, len, PAGE_SIZE - src);
139 memcpy_page(*dst_page, src, *src_page, src, l);
140 set_page_dirty(*dst_page);
141
142 while ((len -= l) != 0) {
143 l = min_t(int, len, PAGE_SIZE);
144 memcpy_page(*++dst_page, 0, *++src_page, 0, l);
145 set_page_dirty(*dst_page);
146 }
147 } else {
148 void *src_ptr, *dst_ptr;
149
150 do {
151 dst_ptr = kmap_local_page(*dst_page) + dst;
152 src_ptr = kmap_local_page(*src_page) + src;
153 if (PAGE_SIZE - src < PAGE_SIZE - dst) {
154 l = PAGE_SIZE - src;
155 src = 0;
156 dst += l;
157 } else {
158 l = PAGE_SIZE - dst;
159 src += l;
160 dst = 0;
161 }
162 l = min(len, l);
163 memcpy(dst_ptr, src_ptr, l);
164 kunmap_local(src_ptr);
165 set_page_dirty(*dst_page);
166 kunmap_local(dst_ptr);
167 if (!dst)
168 dst_page++;
169 else
170 src_page++;
171 } while ((len -= l));
172 }
173}
174
175void hfs_bnode_move(struct hfs_bnode *node, int dst, int src, int len)
176{
177 struct page **src_page, **dst_page;
178 void *src_ptr, *dst_ptr;
179 int l;
180
181 hfs_dbg(BNODE_MOD, "movebytes: %u,%u,%u\n", dst, src, len);
182 if (!len)
183 return;
184 src += node->page_offset;
185 dst += node->page_offset;
186 if (dst > src) {
187 src += len - 1;
188 src_page = node->page + (src >> PAGE_SHIFT);
189 src = (src & ~PAGE_MASK) + 1;
190 dst += len - 1;
191 dst_page = node->page + (dst >> PAGE_SHIFT);
192 dst = (dst & ~PAGE_MASK) + 1;
193
194 if (src == dst) {
195 while (src < len) {
196 dst_ptr = kmap_local_page(*dst_page);
197 src_ptr = kmap_local_page(*src_page);
198 memmove(dst_ptr, src_ptr, src);
199 kunmap_local(src_ptr);
200 set_page_dirty(*dst_page);
201 kunmap_local(dst_ptr);
202 len -= src;
203 src = PAGE_SIZE;
204 src_page--;
205 dst_page--;
206 }
207 src -= len;
208 dst_ptr = kmap_local_page(*dst_page);
209 src_ptr = kmap_local_page(*src_page);
210 memmove(dst_ptr + src, src_ptr + src, len);
211 kunmap_local(src_ptr);
212 set_page_dirty(*dst_page);
213 kunmap_local(dst_ptr);
214 } else {
215 do {
216 dst_ptr = kmap_local_page(*dst_page) + dst;
217 src_ptr = kmap_local_page(*src_page) + src;
218 if (src < dst) {
219 l = src;
220 src = PAGE_SIZE;
221 dst -= l;
222 } else {
223 l = dst;
224 src -= l;
225 dst = PAGE_SIZE;
226 }
227 l = min(len, l);
228 memmove(dst_ptr - l, src_ptr - l, l);
229 kunmap_local(src_ptr);
230 set_page_dirty(*dst_page);
231 kunmap_local(dst_ptr);
232 if (dst == PAGE_SIZE)
233 dst_page--;
234 else
235 src_page--;
236 } while ((len -= l));
237 }
238 } else {
239 src_page = node->page + (src >> PAGE_SHIFT);
240 src &= ~PAGE_MASK;
241 dst_page = node->page + (dst >> PAGE_SHIFT);
242 dst &= ~PAGE_MASK;
243
244 if (src == dst) {
245 l = min_t(int, len, PAGE_SIZE - src);
246
247 dst_ptr = kmap_local_page(*dst_page) + src;
248 src_ptr = kmap_local_page(*src_page) + src;
249 memmove(dst_ptr, src_ptr, l);
250 kunmap_local(src_ptr);
251 set_page_dirty(*dst_page);
252 kunmap_local(dst_ptr);
253
254 while ((len -= l) != 0) {
255 l = min_t(int, len, PAGE_SIZE);
256 dst_ptr = kmap_local_page(*++dst_page);
257 src_ptr = kmap_local_page(*++src_page);
258 memmove(dst_ptr, src_ptr, l);
259 kunmap_local(src_ptr);
260 set_page_dirty(*dst_page);
261 kunmap_local(dst_ptr);
262 }
263 } else {
264 do {
265 dst_ptr = kmap_local_page(*dst_page) + dst;
266 src_ptr = kmap_local_page(*src_page) + src;
267 if (PAGE_SIZE - src <
268 PAGE_SIZE - dst) {
269 l = PAGE_SIZE - src;
270 src = 0;
271 dst += l;
272 } else {
273 l = PAGE_SIZE - dst;
274 src += l;
275 dst = 0;
276 }
277 l = min(len, l);
278 memmove(dst_ptr, src_ptr, l);
279 kunmap_local(src_ptr);
280 set_page_dirty(*dst_page);
281 kunmap_local(dst_ptr);
282 if (!dst)
283 dst_page++;
284 else
285 src_page++;
286 } while ((len -= l));
287 }
288 }
289}
290
291void hfs_bnode_dump(struct hfs_bnode *node)
292{
293 struct hfs_bnode_desc desc;
294 __be32 cnid;
295 int i, off, key_off;
296
297 hfs_dbg(BNODE_MOD, "bnode: %d\n", node->this);
298 hfs_bnode_read(node, &desc, 0, sizeof(desc));
299 hfs_dbg(BNODE_MOD, "%d, %d, %d, %d, %d\n",
300 be32_to_cpu(desc.next), be32_to_cpu(desc.prev),
301 desc.type, desc.height, be16_to_cpu(desc.num_recs));
302
303 off = node->tree->node_size - 2;
304 for (i = be16_to_cpu(desc.num_recs); i >= 0; off -= 2, i--) {
305 key_off = hfs_bnode_read_u16(node, off);
306 hfs_dbg(BNODE_MOD, " %d", key_off);
307 if (i && node->type == HFS_NODE_INDEX) {
308 int tmp;
309
310 if (node->tree->attributes & HFS_TREE_VARIDXKEYS ||
311 node->tree->cnid == HFSPLUS_ATTR_CNID)
312 tmp = hfs_bnode_read_u16(node, key_off) + 2;
313 else
314 tmp = node->tree->max_key_len + 2;
315 hfs_dbg_cont(BNODE_MOD, " (%d", tmp);
316 hfs_bnode_read(node, &cnid, key_off + tmp, 4);
317 hfs_dbg_cont(BNODE_MOD, ",%d)", be32_to_cpu(cnid));
318 } else if (i && node->type == HFS_NODE_LEAF) {
319 int tmp;
320
321 tmp = hfs_bnode_read_u16(node, key_off);
322 hfs_dbg_cont(BNODE_MOD, " (%d)", tmp);
323 }
324 }
325 hfs_dbg_cont(BNODE_MOD, "\n");
326}
327
328void hfs_bnode_unlink(struct hfs_bnode *node)
329{
330 struct hfs_btree *tree;
331 struct hfs_bnode *tmp;
332 __be32 cnid;
333
334 tree = node->tree;
335 if (node->prev) {
336 tmp = hfs_bnode_find(tree, node->prev);
337 if (IS_ERR(tmp))
338 return;
339 tmp->next = node->next;
340 cnid = cpu_to_be32(tmp->next);
341 hfs_bnode_write(tmp, &cnid,
342 offsetof(struct hfs_bnode_desc, next), 4);
343 hfs_bnode_put(tmp);
344 } else if (node->type == HFS_NODE_LEAF)
345 tree->leaf_head = node->next;
346
347 if (node->next) {
348 tmp = hfs_bnode_find(tree, node->next);
349 if (IS_ERR(tmp))
350 return;
351 tmp->prev = node->prev;
352 cnid = cpu_to_be32(tmp->prev);
353 hfs_bnode_write(tmp, &cnid,
354 offsetof(struct hfs_bnode_desc, prev), 4);
355 hfs_bnode_put(tmp);
356 } else if (node->type == HFS_NODE_LEAF)
357 tree->leaf_tail = node->prev;
358
359 /* move down? */
360 if (!node->prev && !node->next)
361 hfs_dbg(BNODE_MOD, "hfs_btree_del_level\n");
362 if (!node->parent) {
363 tree->root = 0;
364 tree->depth = 0;
365 }
366 set_bit(HFS_BNODE_DELETED, &node->flags);
367}
368
369static inline int hfs_bnode_hash(u32 num)
370{
371 num = (num >> 16) + num;
372 num += num >> 8;
373 return num & (NODE_HASH_SIZE - 1);
374}
375
376struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *tree, u32 cnid)
377{
378 struct hfs_bnode *node;
379
380 if (cnid >= tree->node_count) {
381 pr_err("request for non-existent node %d in B*Tree\n",
382 cnid);
383 return NULL;
384 }
385
386 for (node = tree->node_hash[hfs_bnode_hash(cnid)];
387 node; node = node->next_hash)
388 if (node->this == cnid)
389 return node;
390 return NULL;
391}
392
393static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid)
394{
395 struct hfs_bnode *node, *node2;
396 struct address_space *mapping;
397 struct page *page;
398 int size, block, i, hash;
399 loff_t off;
400
401 if (cnid >= tree->node_count) {
402 pr_err("request for non-existent node %d in B*Tree\n",
403 cnid);
404 return NULL;
405 }
406
407 size = sizeof(struct hfs_bnode) + tree->pages_per_bnode *
408 sizeof(struct page *);
409 node = kzalloc(size, GFP_KERNEL);
410 if (!node)
411 return NULL;
412 node->tree = tree;
413 node->this = cnid;
414 set_bit(HFS_BNODE_NEW, &node->flags);
415 atomic_set(&node->refcnt, 1);
416 hfs_dbg(BNODE_REFS, "new_node(%d:%d): 1\n",
417 node->tree->cnid, node->this);
418 init_waitqueue_head(&node->lock_wq);
419 spin_lock(&tree->hash_lock);
420 node2 = hfs_bnode_findhash(tree, cnid);
421 if (!node2) {
422 hash = hfs_bnode_hash(cnid);
423 node->next_hash = tree->node_hash[hash];
424 tree->node_hash[hash] = node;
425 tree->node_hash_cnt++;
426 } else {
427 spin_unlock(&tree->hash_lock);
428 kfree(node);
429 wait_event(node2->lock_wq,
430 !test_bit(HFS_BNODE_NEW, &node2->flags));
431 return node2;
432 }
433 spin_unlock(&tree->hash_lock);
434
435 mapping = tree->inode->i_mapping;
436 off = (loff_t)cnid << tree->node_size_shift;
437 block = off >> PAGE_SHIFT;
438 node->page_offset = off & ~PAGE_MASK;
439 for (i = 0; i < tree->pages_per_bnode; block++, i++) {
440 page = read_mapping_page(mapping, block, NULL);
441 if (IS_ERR(page))
442 goto fail;
443 node->page[i] = page;
444 }
445
446 return node;
447fail:
448 set_bit(HFS_BNODE_ERROR, &node->flags);
449 return node;
450}
451
452void hfs_bnode_unhash(struct hfs_bnode *node)
453{
454 struct hfs_bnode **p;
455
456 hfs_dbg(BNODE_REFS, "remove_node(%d:%d): %d\n",
457 node->tree->cnid, node->this, atomic_read(&node->refcnt));
458 for (p = &node->tree->node_hash[hfs_bnode_hash(node->this)];
459 *p && *p != node; p = &(*p)->next_hash)
460 ;
461 BUG_ON(!*p);
462 *p = node->next_hash;
463 node->tree->node_hash_cnt--;
464}
465
466/* Load a particular node out of a tree */
467struct hfs_bnode *hfs_bnode_find(struct hfs_btree *tree, u32 num)
468{
469 struct hfs_bnode *node;
470 struct hfs_bnode_desc *desc;
471 int i, rec_off, off, next_off;
472 int entry_size, key_size;
473
474 spin_lock(&tree->hash_lock);
475 node = hfs_bnode_findhash(tree, num);
476 if (node) {
477 hfs_bnode_get(node);
478 spin_unlock(&tree->hash_lock);
479 wait_event(node->lock_wq,
480 !test_bit(HFS_BNODE_NEW, &node->flags));
481 if (test_bit(HFS_BNODE_ERROR, &node->flags))
482 goto node_error;
483 return node;
484 }
485 spin_unlock(&tree->hash_lock);
486 node = __hfs_bnode_create(tree, num);
487 if (!node)
488 return ERR_PTR(-ENOMEM);
489 if (test_bit(HFS_BNODE_ERROR, &node->flags))
490 goto node_error;
491 if (!test_bit(HFS_BNODE_NEW, &node->flags))
492 return node;
493
494 desc = (struct hfs_bnode_desc *)(kmap_local_page(node->page[0]) +
495 node->page_offset);
496 node->prev = be32_to_cpu(desc->prev);
497 node->next = be32_to_cpu(desc->next);
498 node->num_recs = be16_to_cpu(desc->num_recs);
499 node->type = desc->type;
500 node->height = desc->height;
501 kunmap_local(desc);
502
503 switch (node->type) {
504 case HFS_NODE_HEADER:
505 case HFS_NODE_MAP:
506 if (node->height != 0)
507 goto node_error;
508 break;
509 case HFS_NODE_LEAF:
510 if (node->height != 1)
511 goto node_error;
512 break;
513 case HFS_NODE_INDEX:
514 if (node->height <= 1 || node->height > tree->depth)
515 goto node_error;
516 break;
517 default:
518 goto node_error;
519 }
520
521 rec_off = tree->node_size - 2;
522 off = hfs_bnode_read_u16(node, rec_off);
523 if (off != sizeof(struct hfs_bnode_desc))
524 goto node_error;
525 for (i = 1; i <= node->num_recs; off = next_off, i++) {
526 rec_off -= 2;
527 next_off = hfs_bnode_read_u16(node, rec_off);
528 if (next_off <= off ||
529 next_off > tree->node_size ||
530 next_off & 1)
531 goto node_error;
532 entry_size = next_off - off;
533 if (node->type != HFS_NODE_INDEX &&
534 node->type != HFS_NODE_LEAF)
535 continue;
536 key_size = hfs_bnode_read_u16(node, off) + 2;
537 if (key_size >= entry_size || key_size & 1)
538 goto node_error;
539 }
540 clear_bit(HFS_BNODE_NEW, &node->flags);
541 wake_up(&node->lock_wq);
542 return node;
543
544node_error:
545 set_bit(HFS_BNODE_ERROR, &node->flags);
546 clear_bit(HFS_BNODE_NEW, &node->flags);
547 wake_up(&node->lock_wq);
548 hfs_bnode_put(node);
549 return ERR_PTR(-EIO);
550}
551
552void hfs_bnode_free(struct hfs_bnode *node)
553{
554 int i;
555
556 for (i = 0; i < node->tree->pages_per_bnode; i++)
557 if (node->page[i])
558 put_page(node->page[i]);
559 kfree(node);
560}
561
562struct hfs_bnode *hfs_bnode_create(struct hfs_btree *tree, u32 num)
563{
564 struct hfs_bnode *node;
565 struct page **pagep;
566 int i;
567
568 spin_lock(&tree->hash_lock);
569 node = hfs_bnode_findhash(tree, num);
570 spin_unlock(&tree->hash_lock);
571 if (node) {
572 pr_crit("new node %u already hashed?\n", num);
573 WARN_ON(1);
574 return node;
575 }
576 node = __hfs_bnode_create(tree, num);
577 if (!node)
578 return ERR_PTR(-ENOMEM);
579 if (test_bit(HFS_BNODE_ERROR, &node->flags)) {
580 hfs_bnode_put(node);
581 return ERR_PTR(-EIO);
582 }
583
584 pagep = node->page;
585 memzero_page(*pagep, node->page_offset,
586 min_t(int, PAGE_SIZE, tree->node_size));
587 set_page_dirty(*pagep);
588 for (i = 1; i < tree->pages_per_bnode; i++) {
589 memzero_page(*++pagep, 0, PAGE_SIZE);
590 set_page_dirty(*pagep);
591 }
592 clear_bit(HFS_BNODE_NEW, &node->flags);
593 wake_up(&node->lock_wq);
594
595 return node;
596}
597
598void hfs_bnode_get(struct hfs_bnode *node)
599{
600 if (node) {
601 atomic_inc(&node->refcnt);
602 hfs_dbg(BNODE_REFS, "get_node(%d:%d): %d\n",
603 node->tree->cnid, node->this,
604 atomic_read(&node->refcnt));
605 }
606}
607
608/* Dispose of resources used by a node */
609void hfs_bnode_put(struct hfs_bnode *node)
610{
611 if (node) {
612 struct hfs_btree *tree = node->tree;
613 int i;
614
615 hfs_dbg(BNODE_REFS, "put_node(%d:%d): %d\n",
616 node->tree->cnid, node->this,
617 atomic_read(&node->refcnt));
618 BUG_ON(!atomic_read(&node->refcnt));
619 if (!atomic_dec_and_lock(&node->refcnt, &tree->hash_lock))
620 return;
621 for (i = 0; i < tree->pages_per_bnode; i++) {
622 if (!node->page[i])
623 continue;
624 mark_page_accessed(node->page[i]);
625 }
626
627 if (test_bit(HFS_BNODE_DELETED, &node->flags)) {
628 hfs_bnode_unhash(node);
629 spin_unlock(&tree->hash_lock);
630 if (hfs_bnode_need_zeroout(tree))
631 hfs_bnode_clear(node, 0, tree->node_size);
632 hfs_bmap_free(node);
633 hfs_bnode_free(node);
634 return;
635 }
636 spin_unlock(&tree->hash_lock);
637 }
638}
639
640/*
641 * Unused nodes have to be zeroed if this is the catalog tree and
642 * a corresponding flag in the volume header is set.
643 */
644bool hfs_bnode_need_zeroout(struct hfs_btree *tree)
645{
646 struct super_block *sb = tree->inode->i_sb;
647 struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
648 const u32 volume_attr = be32_to_cpu(sbi->s_vhdr->attributes);
649
650 return tree->cnid == HFSPLUS_CAT_CNID &&
651 volume_attr & HFSPLUS_VOL_UNUSED_NODE_FIX;
652}