2 * linux/fs/hfsplus/bnode.c
5 * Brad Boyer (flar@allandria.com)
6 * (C) 2003 Ardis Technologies <roman@ardistech.com>
8 * Handle basic btree node operations
11 #include <linux/string.h>
12 #include <linux/slab.h>
13 #include <linux/pagemap.h>
15 #include <linux/swap.h>
17 #include "hfsplus_fs.h"
18 #include "hfsplus_raw.h"
20 /* Copy a specified range of bytes from the raw data of a node */
21 void hfs_bnode_read(struct hfs_bnode
*node
, void *buf
, int off
, int len
)
26 off
+= node
->page_offset
;
27 pagep
= node
->page
+ (off
>> PAGE_CACHE_SHIFT
);
28 off
&= ~PAGE_CACHE_MASK
;
30 l
= min(len
, (int)PAGE_CACHE_SIZE
- off
);
31 memcpy(buf
, kmap(*pagep
) + off
, l
);
34 while ((len
-= l
) != 0) {
36 l
= min(len
, (int)PAGE_CACHE_SIZE
);
37 memcpy(buf
, kmap(*++pagep
), l
);
42 u16
hfs_bnode_read_u16(struct hfs_bnode
*node
, int off
)
45 /* TODO: optimize later... */
46 hfs_bnode_read(node
, &data
, off
, 2);
47 return be16_to_cpu(data
);
50 u8
hfs_bnode_read_u8(struct hfs_bnode
*node
, int off
)
53 /* TODO: optimize later... */
54 hfs_bnode_read(node
, &data
, off
, 1);
58 void hfs_bnode_read_key(struct hfs_bnode
*node
, void *key
, int off
)
60 struct hfs_btree
*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;
69 key_len
= tree
->max_key_len
+ 2;
71 hfs_bnode_read(node
, key
, off
, key_len
);
74 void hfs_bnode_write(struct hfs_bnode
*node
, void *buf
, int off
, int len
)
79 off
+= node
->page_offset
;
80 pagep
= node
->page
+ (off
>> PAGE_CACHE_SHIFT
);
81 off
&= ~PAGE_CACHE_MASK
;
83 l
= min(len
, (int)PAGE_CACHE_SIZE
- off
);
84 memcpy(kmap(*pagep
) + off
, buf
, l
);
85 set_page_dirty(*pagep
);
88 while ((len
-= l
) != 0) {
90 l
= min(len
, (int)PAGE_CACHE_SIZE
);
91 memcpy(kmap(*++pagep
), buf
, l
);
92 set_page_dirty(*pagep
);
97 void hfs_bnode_write_u16(struct hfs_bnode
*node
, int off
, u16 data
)
99 __be16 v
= cpu_to_be16(data
);
100 /* TODO: optimize later... */
101 hfs_bnode_write(node
, &v
, off
, 2);
104 void hfs_bnode_clear(struct hfs_bnode
*node
, int off
, int len
)
109 off
+= node
->page_offset
;
110 pagep
= node
->page
+ (off
>> PAGE_CACHE_SHIFT
);
111 off
&= ~PAGE_CACHE_MASK
;
113 l
= min(len
, (int)PAGE_CACHE_SIZE
- off
);
114 memset(kmap(*pagep
) + off
, 0, l
);
115 set_page_dirty(*pagep
);
118 while ((len
-= l
) != 0) {
119 l
= min(len
, (int)PAGE_CACHE_SIZE
);
120 memset(kmap(*++pagep
), 0, l
);
121 set_page_dirty(*pagep
);
126 void hfs_bnode_copy(struct hfs_bnode
*dst_node
, int dst
,
127 struct hfs_bnode
*src_node
, int src
, int len
)
129 struct hfs_btree
*tree
;
130 struct page
**src_page
, **dst_page
;
133 hfs_dbg(BNODE_MOD
, "copybytes: %u,%u,%u\n", dst
, src
, len
);
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_CACHE_SHIFT
);
140 src
&= ~PAGE_CACHE_MASK
;
141 dst_page
= dst_node
->page
+ (dst
>> PAGE_CACHE_SHIFT
);
142 dst
&= ~PAGE_CACHE_MASK
;
145 l
= min(len
, (int)PAGE_CACHE_SIZE
- src
);
146 memcpy(kmap(*dst_page
) + src
, kmap(*src_page
) + src
, l
);
148 set_page_dirty(*dst_page
);
151 while ((len
-= l
) != 0) {
152 l
= min(len
, (int)PAGE_CACHE_SIZE
);
153 memcpy(kmap(*++dst_page
), kmap(*++src_page
), l
);
155 set_page_dirty(*dst_page
);
159 void *src_ptr
, *dst_ptr
;
162 src_ptr
= kmap(*src_page
) + src
;
163 dst_ptr
= kmap(*dst_page
) + dst
;
164 if (PAGE_CACHE_SIZE
- src
< PAGE_CACHE_SIZE
- dst
) {
165 l
= PAGE_CACHE_SIZE
- src
;
169 l
= PAGE_CACHE_SIZE
- dst
;
174 memcpy(dst_ptr
, src_ptr
, l
);
176 set_page_dirty(*dst_page
);
182 } while ((len
-= l
));
186 void hfs_bnode_move(struct hfs_bnode
*node
, int dst
, int src
, int len
)
188 struct page
**src_page
, **dst_page
;
191 hfs_dbg(BNODE_MOD
, "movebytes: %u,%u,%u\n", dst
, src
, len
);
194 src
+= node
->page_offset
;
195 dst
+= node
->page_offset
;
198 src_page
= node
->page
+ (src
>> PAGE_CACHE_SHIFT
);
199 src
= (src
& ~PAGE_CACHE_MASK
) + 1;
201 dst_page
= node
->page
+ (dst
>> PAGE_CACHE_SHIFT
);
202 dst
= (dst
& ~PAGE_CACHE_MASK
) + 1;
206 memmove(kmap(*dst_page
), kmap(*src_page
), src
);
208 set_page_dirty(*dst_page
);
211 src
= PAGE_CACHE_SIZE
;
216 memmove(kmap(*dst_page
) + src
,
217 kmap(*src_page
) + src
, len
);
219 set_page_dirty(*dst_page
);
222 void *src_ptr
, *dst_ptr
;
225 src_ptr
= kmap(*src_page
) + src
;
226 dst_ptr
= kmap(*dst_page
) + dst
;
229 src
= PAGE_CACHE_SIZE
;
234 dst
= PAGE_CACHE_SIZE
;
237 memmove(dst_ptr
- l
, src_ptr
- l
, l
);
239 set_page_dirty(*dst_page
);
241 if (dst
== PAGE_CACHE_SIZE
)
245 } while ((len
-= l
));
248 src_page
= node
->page
+ (src
>> PAGE_CACHE_SHIFT
);
249 src
&= ~PAGE_CACHE_MASK
;
250 dst_page
= node
->page
+ (dst
>> PAGE_CACHE_SHIFT
);
251 dst
&= ~PAGE_CACHE_MASK
;
254 l
= min(len
, (int)PAGE_CACHE_SIZE
- src
);
255 memmove(kmap(*dst_page
) + src
,
256 kmap(*src_page
) + src
, l
);
258 set_page_dirty(*dst_page
);
261 while ((len
-= l
) != 0) {
262 l
= min(len
, (int)PAGE_CACHE_SIZE
);
263 memmove(kmap(*++dst_page
),
264 kmap(*++src_page
), l
);
266 set_page_dirty(*dst_page
);
270 void *src_ptr
, *dst_ptr
;
273 src_ptr
= kmap(*src_page
) + src
;
274 dst_ptr
= kmap(*dst_page
) + dst
;
275 if (PAGE_CACHE_SIZE
- src
<
276 PAGE_CACHE_SIZE
- dst
) {
277 l
= PAGE_CACHE_SIZE
- src
;
281 l
= PAGE_CACHE_SIZE
- dst
;
286 memmove(dst_ptr
, src_ptr
, l
);
288 set_page_dirty(*dst_page
);
294 } while ((len
-= l
));
299 void hfs_bnode_dump(struct hfs_bnode
*node
)
301 struct hfs_bnode_desc desc
;
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
));
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
) {
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;
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
) {
329 tmp
= hfs_bnode_read_u16(node
, key_off
);
330 hfs_dbg_cont(BNODE_MOD
, " (%d)", tmp
);
333 hfs_dbg_cont(BNODE_MOD
, "\n");
336 void hfs_bnode_unlink(struct hfs_bnode
*node
)
338 struct hfs_btree
*tree
;
339 struct hfs_bnode
*tmp
;
344 tmp
= hfs_bnode_find(tree
, node
->prev
);
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);
352 } else if (node
->type
== HFS_NODE_LEAF
)
353 tree
->leaf_head
= node
->next
;
356 tmp
= hfs_bnode_find(tree
, node
->next
);
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);
364 } else if (node
->type
== HFS_NODE_LEAF
)
365 tree
->leaf_tail
= node
->prev
;
368 if (!node
->prev
&& !node
->next
)
369 hfs_dbg(BNODE_MOD
, "hfs_btree_del_level\n");
374 set_bit(HFS_BNODE_DELETED
, &node
->flags
);
377 static inline int hfs_bnode_hash(u32 num
)
379 num
= (num
>> 16) + num
;
381 return num
& (NODE_HASH_SIZE
- 1);
384 struct hfs_bnode
*hfs_bnode_findhash(struct hfs_btree
*tree
, u32 cnid
)
386 struct hfs_bnode
*node
;
388 if (cnid
>= tree
->node_count
) {
389 pr_err("request for non-existent node "
395 for (node
= tree
->node_hash
[hfs_bnode_hash(cnid
)];
396 node
; node
= node
->next_hash
)
397 if (node
->this == cnid
)
402 static struct hfs_bnode
*__hfs_bnode_create(struct hfs_btree
*tree
, u32 cnid
)
404 struct super_block
*sb
;
405 struct hfs_bnode
*node
, *node2
;
406 struct address_space
*mapping
;
408 int size
, block
, i
, hash
;
411 if (cnid
>= tree
->node_count
) {
412 pr_err("request for non-existent node "
418 sb
= tree
->inode
->i_sb
;
419 size
= sizeof(struct hfs_bnode
) + tree
->pages_per_bnode
*
420 sizeof(struct page
*);
421 node
= kzalloc(size
, GFP_KERNEL
);
426 set_bit(HFS_BNODE_NEW
, &node
->flags
);
427 atomic_set(&node
->refcnt
, 1);
428 hfs_dbg(BNODE_REFS
, "new_node(%d:%d): 1\n",
429 node
->tree
->cnid
, node
->this);
430 init_waitqueue_head(&node
->lock_wq
);
431 spin_lock(&tree
->hash_lock
);
432 node2
= hfs_bnode_findhash(tree
, cnid
);
434 hash
= hfs_bnode_hash(cnid
);
435 node
->next_hash
= tree
->node_hash
[hash
];
436 tree
->node_hash
[hash
] = node
;
437 tree
->node_hash_cnt
++;
439 spin_unlock(&tree
->hash_lock
);
441 wait_event(node2
->lock_wq
,
442 !test_bit(HFS_BNODE_NEW
, &node2
->flags
));
445 spin_unlock(&tree
->hash_lock
);
447 mapping
= tree
->inode
->i_mapping
;
448 off
= (loff_t
)cnid
<< tree
->node_size_shift
;
449 block
= off
>> PAGE_CACHE_SHIFT
;
450 node
->page_offset
= off
& ~PAGE_CACHE_MASK
;
451 for (i
= 0; i
< tree
->pages_per_bnode
; block
++, i
++) {
452 page
= read_mapping_page(mapping
, block
, NULL
);
455 if (PageError(page
)) {
456 page_cache_release(page
);
459 page_cache_release(page
);
460 node
->page
[i
] = page
;
465 set_bit(HFS_BNODE_ERROR
, &node
->flags
);
469 void hfs_bnode_unhash(struct hfs_bnode
*node
)
471 struct hfs_bnode
**p
;
473 hfs_dbg(BNODE_REFS
, "remove_node(%d:%d): %d\n",
474 node
->tree
->cnid
, node
->this, atomic_read(&node
->refcnt
));
475 for (p
= &node
->tree
->node_hash
[hfs_bnode_hash(node
->this)];
476 *p
&& *p
!= node
; p
= &(*p
)->next_hash
)
479 *p
= node
->next_hash
;
480 node
->tree
->node_hash_cnt
--;
483 /* Load a particular node out of a tree */
484 struct hfs_bnode
*hfs_bnode_find(struct hfs_btree
*tree
, u32 num
)
486 struct hfs_bnode
*node
;
487 struct hfs_bnode_desc
*desc
;
488 int i
, rec_off
, off
, next_off
;
489 int entry_size
, key_size
;
491 spin_lock(&tree
->hash_lock
);
492 node
= hfs_bnode_findhash(tree
, num
);
495 spin_unlock(&tree
->hash_lock
);
496 wait_event(node
->lock_wq
,
497 !test_bit(HFS_BNODE_NEW
, &node
->flags
));
498 if (test_bit(HFS_BNODE_ERROR
, &node
->flags
))
502 spin_unlock(&tree
->hash_lock
);
503 node
= __hfs_bnode_create(tree
, num
);
505 return ERR_PTR(-ENOMEM
);
506 if (test_bit(HFS_BNODE_ERROR
, &node
->flags
))
508 if (!test_bit(HFS_BNODE_NEW
, &node
->flags
))
511 desc
= (struct hfs_bnode_desc
*)(kmap(node
->page
[0]) +
513 node
->prev
= be32_to_cpu(desc
->prev
);
514 node
->next
= be32_to_cpu(desc
->next
);
515 node
->num_recs
= be16_to_cpu(desc
->num_recs
);
516 node
->type
= desc
->type
;
517 node
->height
= desc
->height
;
518 kunmap(node
->page
[0]);
520 switch (node
->type
) {
521 case HFS_NODE_HEADER
:
523 if (node
->height
!= 0)
527 if (node
->height
!= 1)
531 if (node
->height
<= 1 || node
->height
> tree
->depth
)
538 rec_off
= tree
->node_size
- 2;
539 off
= hfs_bnode_read_u16(node
, rec_off
);
540 if (off
!= sizeof(struct hfs_bnode_desc
))
542 for (i
= 1; i
<= node
->num_recs
; off
= next_off
, i
++) {
544 next_off
= hfs_bnode_read_u16(node
, rec_off
);
545 if (next_off
<= off
||
546 next_off
> tree
->node_size
||
549 entry_size
= next_off
- off
;
550 if (node
->type
!= HFS_NODE_INDEX
&&
551 node
->type
!= HFS_NODE_LEAF
)
553 key_size
= hfs_bnode_read_u16(node
, off
) + 2;
554 if (key_size
>= entry_size
|| key_size
& 1)
557 clear_bit(HFS_BNODE_NEW
, &node
->flags
);
558 wake_up(&node
->lock_wq
);
562 set_bit(HFS_BNODE_ERROR
, &node
->flags
);
563 clear_bit(HFS_BNODE_NEW
, &node
->flags
);
564 wake_up(&node
->lock_wq
);
566 return ERR_PTR(-EIO
);
569 void hfs_bnode_free(struct hfs_bnode
*node
)
574 for (i
= 0; i
< node
->tree
->pages_per_bnode
; i
++)
576 page_cache_release(node
->page
[i
]);
581 struct hfs_bnode
*hfs_bnode_create(struct hfs_btree
*tree
, u32 num
)
583 struct hfs_bnode
*node
;
587 spin_lock(&tree
->hash_lock
);
588 node
= hfs_bnode_findhash(tree
, num
);
589 spin_unlock(&tree
->hash_lock
);
591 pr_crit("new node %u already hashed?\n", num
);
595 node
= __hfs_bnode_create(tree
, num
);
597 return ERR_PTR(-ENOMEM
);
598 if (test_bit(HFS_BNODE_ERROR
, &node
->flags
)) {
600 return ERR_PTR(-EIO
);
604 memset(kmap(*pagep
) + node
->page_offset
, 0,
605 min((int)PAGE_CACHE_SIZE
, (int)tree
->node_size
));
606 set_page_dirty(*pagep
);
608 for (i
= 1; i
< tree
->pages_per_bnode
; i
++) {
609 memset(kmap(*++pagep
), 0, PAGE_CACHE_SIZE
);
610 set_page_dirty(*pagep
);
613 clear_bit(HFS_BNODE_NEW
, &node
->flags
);
614 wake_up(&node
->lock_wq
);
619 void hfs_bnode_get(struct hfs_bnode
*node
)
622 atomic_inc(&node
->refcnt
);
623 hfs_dbg(BNODE_REFS
, "get_node(%d:%d): %d\n",
624 node
->tree
->cnid
, node
->this,
625 atomic_read(&node
->refcnt
));
629 /* Dispose of resources used by a node */
630 void hfs_bnode_put(struct hfs_bnode
*node
)
633 struct hfs_btree
*tree
= node
->tree
;
636 hfs_dbg(BNODE_REFS
, "put_node(%d:%d): %d\n",
637 node
->tree
->cnid
, node
->this,
638 atomic_read(&node
->refcnt
));
639 BUG_ON(!atomic_read(&node
->refcnt
));
640 if (!atomic_dec_and_lock(&node
->refcnt
, &tree
->hash_lock
))
642 for (i
= 0; i
< tree
->pages_per_bnode
; i
++) {
645 mark_page_accessed(node
->page
[i
]);
648 if (test_bit(HFS_BNODE_DELETED
, &node
->flags
)) {
649 hfs_bnode_unhash(node
);
650 spin_unlock(&tree
->hash_lock
);
651 hfs_bnode_clear(node
, 0,
652 PAGE_CACHE_SIZE
* tree
->pages_per_bnode
);
654 hfs_bnode_free(node
);
657 spin_unlock(&tree
->hash_lock
);