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 */ |
22 | void 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(to: buf, page: *pagep, offset: off, len: l); |
33 | |
34 | while ((len -= l) != 0) { |
35 | buf += l; |
36 | l = min_t(int, len, PAGE_SIZE); |
37 | memcpy_from_page(to: buf, page: *++pagep, offset: 0, len: l); |
38 | } |
39 | } |
40 | |
41 | u16 hfs_bnode_read_u16(struct hfs_bnode *node, int off) |
42 | { |
43 | __be16 data; |
44 | /* TODO: optimize later... */ |
45 | hfs_bnode_read(node, buf: &data, off, len: 2); |
46 | return be16_to_cpu(data); |
47 | } |
48 | |
49 | u8 hfs_bnode_read_u8(struct hfs_bnode *node, int off) |
50 | { |
51 | u8 data; |
52 | /* TODO: optimize later... */ |
53 | hfs_bnode_read(node, buf: &data, off, len: 1); |
54 | return data; |
55 | } |
56 | |
57 | void 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, buf: key, off, len: key_len); |
71 | } |
72 | |
73 | void 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(page: *pagep, offset: off, from: buf, len: 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(page: *++pagep, offset: 0, from: buf, len: l); |
90 | set_page_dirty(*pagep); |
91 | } |
92 | } |
93 | |
94 | void 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, buf: &v, off, len: 2); |
99 | } |
100 | |
101 | void 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(page: *pagep, offset: off, len: l); |
112 | set_page_dirty(*pagep); |
113 | |
114 | while ((len -= l) != 0) { |
115 | l = min_t(int, len, PAGE_SIZE); |
116 | memzero_page(page: *++pagep, offset: 0, len: l); |
117 | set_page_dirty(*pagep); |
118 | } |
119 | } |
120 | |
121 | void 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: *dst_page, dst_off: src, src_page: *src_page, src_off: src, len: 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: *++dst_page, dst_off: 0, src_page: *++src_page, src_off: 0, len: 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(page: *dst_page) + dst; |
152 | src_ptr = kmap_local_page(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 | |
175 | void 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(page: *dst_page); |
197 | src_ptr = kmap_local_page(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(page: *dst_page); |
209 | src_ptr = kmap_local_page(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(page: *dst_page) + dst; |
217 | src_ptr = kmap_local_page(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(page: *dst_page) + src; |
248 | src_ptr = kmap_local_page(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(page: *++dst_page); |
257 | src_ptr = kmap_local_page(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(page: *dst_page) + dst; |
266 | src_ptr = kmap_local_page(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 | |
291 | void 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, buf: &desc, off: 0, len: 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, off: 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, buf: &cnid, off: key_off + tmp, len: 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, off: key_off); |
322 | hfs_dbg_cont(BNODE_MOD, " (%d)" , tmp); |
323 | } |
324 | } |
325 | hfs_dbg_cont(BNODE_MOD, "\n" ); |
326 | } |
327 | |
328 | void 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, num: node->prev); |
337 | if (IS_ERR(ptr: tmp)) |
338 | return; |
339 | tmp->next = node->next; |
340 | cnid = cpu_to_be32(tmp->next); |
341 | hfs_bnode_write(node: tmp, buf: &cnid, |
342 | offsetof(struct hfs_bnode_desc, next), len: 4); |
343 | hfs_bnode_put(node: 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, num: node->next); |
349 | if (IS_ERR(ptr: tmp)) |
350 | return; |
351 | tmp->prev = node->prev; |
352 | cnid = cpu_to_be32(tmp->prev); |
353 | hfs_bnode_write(node: tmp, buf: &cnid, |
354 | offsetof(struct hfs_bnode_desc, prev), len: 4); |
355 | hfs_bnode_put(node: 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, addr: &node->flags); |
367 | } |
368 | |
369 | static 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 | |
376 | struct 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(num: cnid)]; |
387 | node; node = node->next_hash) |
388 | if (node->this == cnid) |
389 | return node; |
390 | return NULL; |
391 | } |
392 | |
393 | static 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, addr: &node->flags); |
415 | atomic_set(v: &node->refcnt, i: 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(lock: &tree->hash_lock); |
420 | node2 = hfs_bnode_findhash(tree, cnid); |
421 | if (!node2) { |
422 | hash = hfs_bnode_hash(num: 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(lock: &tree->hash_lock); |
428 | kfree(objp: node); |
429 | wait_event(node2->lock_wq, |
430 | !test_bit(HFS_BNODE_NEW, &node2->flags)); |
431 | return node2; |
432 | } |
433 | spin_unlock(lock: &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, index: block, NULL); |
441 | if (IS_ERR(ptr: page)) |
442 | goto fail; |
443 | node->page[i] = page; |
444 | } |
445 | |
446 | return node; |
447 | fail: |
448 | set_bit(HFS_BNODE_ERROR, addr: &node->flags); |
449 | return node; |
450 | } |
451 | |
452 | void 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(num: 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 */ |
467 | struct 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(lock: &tree->hash_lock); |
475 | node = hfs_bnode_findhash(tree, cnid: num); |
476 | if (node) { |
477 | hfs_bnode_get(node); |
478 | spin_unlock(lock: &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(lock: &tree->hash_lock); |
486 | node = __hfs_bnode_create(tree, cnid: num); |
487 | if (!node) |
488 | return ERR_PTR(error: -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(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, off: 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, off: 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, addr: &node->flags); |
541 | wake_up(&node->lock_wq); |
542 | return node; |
543 | |
544 | node_error: |
545 | set_bit(HFS_BNODE_ERROR, addr: &node->flags); |
546 | clear_bit(HFS_BNODE_NEW, addr: &node->flags); |
547 | wake_up(&node->lock_wq); |
548 | hfs_bnode_put(node); |
549 | return ERR_PTR(error: -EIO); |
550 | } |
551 | |
552 | void 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(page: node->page[i]); |
559 | kfree(objp: node); |
560 | } |
561 | |
562 | struct 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(lock: &tree->hash_lock); |
569 | node = hfs_bnode_findhash(tree, cnid: num); |
570 | spin_unlock(lock: &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, cnid: num); |
577 | if (!node) |
578 | return ERR_PTR(error: -ENOMEM); |
579 | if (test_bit(HFS_BNODE_ERROR, &node->flags)) { |
580 | hfs_bnode_put(node); |
581 | return ERR_PTR(error: -EIO); |
582 | } |
583 | |
584 | pagep = node->page; |
585 | memzero_page(page: *pagep, offset: 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(page: *++pagep, offset: 0, PAGE_SIZE); |
590 | set_page_dirty(*pagep); |
591 | } |
592 | clear_bit(HFS_BNODE_NEW, addr: &node->flags); |
593 | wake_up(&node->lock_wq); |
594 | |
595 | return node; |
596 | } |
597 | |
598 | void hfs_bnode_get(struct hfs_bnode *node) |
599 | { |
600 | if (node) { |
601 | atomic_inc(v: &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 */ |
609 | void 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(lock: &tree->hash_lock); |
630 | if (hfs_bnode_need_zeroout(tree)) |
631 | hfs_bnode_clear(node, off: 0, len: tree->node_size); |
632 | hfs_bmap_free(node); |
633 | hfs_bnode_free(node); |
634 | return; |
635 | } |
636 | spin_unlock(lock: &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 | */ |
644 | bool 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 | } |
653 | |