1 // SPDX-License-Identifier: GPL-2.0
3 * linux/fs/hfsplus/bnode.c
6 * Brad Boyer (flar@allandria.com)
7 * (C) 2003 Ardis Technologies <roman@ardistech.com>
9 * Handle basic btree node operations
12 #include <linux/string.h>
13 #include <linux/slab.h>
14 #include <linux/pagemap.h>
16 #include <linux/swap.h>
18 #include "hfsplus_fs.h"
19 #include "hfsplus_raw.h"
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
)
27 off
+= node
->page_offset
;
28 pagep
= node
->page
+ (off
>> PAGE_SHIFT
);
31 l
= min_t(int, len
, PAGE_SIZE
- off
);
32 memcpy(buf
, kmap(*pagep
) + off
, l
);
35 while ((len
-= l
) != 0) {
37 l
= min_t(int, len
, PAGE_SIZE
);
38 memcpy(buf
, kmap(*++pagep
), l
);
43 u16
hfs_bnode_read_u16(struct hfs_bnode
*node
, int off
)
46 /* TODO: optimize later... */
47 hfs_bnode_read(node
, &data
, off
, 2);
48 return be16_to_cpu(data
);
51 u8
hfs_bnode_read_u8(struct hfs_bnode
*node
, int off
)
54 /* TODO: optimize later... */
55 hfs_bnode_read(node
, &data
, off
, 1);
59 void hfs_bnode_read_key(struct hfs_bnode
*node
, void *key
, int off
)
61 struct hfs_btree
*tree
;
65 if (node
->type
== HFS_NODE_LEAF
||
66 tree
->attributes
& HFS_TREE_VARIDXKEYS
||
67 node
->tree
->cnid
== HFSPLUS_ATTR_CNID
)
68 key_len
= hfs_bnode_read_u16(node
, off
) + 2;
70 key_len
= tree
->max_key_len
+ 2;
72 hfs_bnode_read(node
, key
, off
, key_len
);
75 void hfs_bnode_write(struct hfs_bnode
*node
, void *buf
, int off
, int len
)
80 off
+= node
->page_offset
;
81 pagep
= node
->page
+ (off
>> PAGE_SHIFT
);
84 l
= min_t(int, len
, PAGE_SIZE
- off
);
85 memcpy(kmap(*pagep
) + off
, buf
, l
);
86 set_page_dirty(*pagep
);
89 while ((len
-= l
) != 0) {
91 l
= min_t(int, len
, PAGE_SIZE
);
92 memcpy(kmap(*++pagep
), buf
, l
);
93 set_page_dirty(*pagep
);
98 void hfs_bnode_write_u16(struct hfs_bnode
*node
, int off
, u16 data
)
100 __be16 v
= cpu_to_be16(data
);
101 /* TODO: optimize later... */
102 hfs_bnode_write(node
, &v
, off
, 2);
105 void hfs_bnode_clear(struct hfs_bnode
*node
, int off
, int len
)
110 off
+= node
->page_offset
;
111 pagep
= node
->page
+ (off
>> PAGE_SHIFT
);
114 l
= min_t(int, len
, PAGE_SIZE
- off
);
115 memset(kmap(*pagep
) + off
, 0, l
);
116 set_page_dirty(*pagep
);
119 while ((len
-= l
) != 0) {
120 l
= min_t(int, len
, PAGE_SIZE
);
121 memset(kmap(*++pagep
), 0, l
);
122 set_page_dirty(*pagep
);
127 void hfs_bnode_copy(struct hfs_bnode
*dst_node
, int dst
,
128 struct hfs_bnode
*src_node
, int src
, int len
)
130 struct page
**src_page
, **dst_page
;
133 hfs_dbg(BNODE_MOD
, "copybytes: %u,%u,%u\n", dst
, src
, len
);
136 src
+= src_node
->page_offset
;
137 dst
+= dst_node
->page_offset
;
138 src_page
= src_node
->page
+ (src
>> PAGE_SHIFT
);
140 dst_page
= dst_node
->page
+ (dst
>> PAGE_SHIFT
);
144 l
= min_t(int, len
, PAGE_SIZE
- src
);
145 memcpy(kmap(*dst_page
) + src
, kmap(*src_page
) + src
, l
);
147 set_page_dirty(*dst_page
);
150 while ((len
-= l
) != 0) {
151 l
= min_t(int, len
, PAGE_SIZE
);
152 memcpy(kmap(*++dst_page
), kmap(*++src_page
), l
);
154 set_page_dirty(*dst_page
);
158 void *src_ptr
, *dst_ptr
;
161 src_ptr
= kmap(*src_page
) + src
;
162 dst_ptr
= kmap(*dst_page
) + dst
;
163 if (PAGE_SIZE
- src
< PAGE_SIZE
- dst
) {
173 memcpy(dst_ptr
, src_ptr
, l
);
175 set_page_dirty(*dst_page
);
181 } while ((len
-= l
));
185 void hfs_bnode_move(struct hfs_bnode
*node
, int dst
, int src
, int len
)
187 struct page
**src_page
, **dst_page
;
190 hfs_dbg(BNODE_MOD
, "movebytes: %u,%u,%u\n", dst
, src
, len
);
193 src
+= node
->page_offset
;
194 dst
+= node
->page_offset
;
197 src_page
= node
->page
+ (src
>> PAGE_SHIFT
);
198 src
= (src
& ~PAGE_MASK
) + 1;
200 dst_page
= node
->page
+ (dst
>> PAGE_SHIFT
);
201 dst
= (dst
& ~PAGE_MASK
) + 1;
205 memmove(kmap(*dst_page
), kmap(*src_page
), src
);
207 set_page_dirty(*dst_page
);
215 memmove(kmap(*dst_page
) + src
,
216 kmap(*src_page
) + src
, len
);
218 set_page_dirty(*dst_page
);
221 void *src_ptr
, *dst_ptr
;
224 src_ptr
= kmap(*src_page
) + src
;
225 dst_ptr
= kmap(*dst_page
) + dst
;
236 memmove(dst_ptr
- l
, src_ptr
- l
, l
);
238 set_page_dirty(*dst_page
);
240 if (dst
== PAGE_SIZE
)
244 } while ((len
-= l
));
247 src_page
= node
->page
+ (src
>> PAGE_SHIFT
);
249 dst_page
= node
->page
+ (dst
>> PAGE_SHIFT
);
253 l
= min_t(int, len
, PAGE_SIZE
- src
);
254 memmove(kmap(*dst_page
) + src
,
255 kmap(*src_page
) + src
, l
);
257 set_page_dirty(*dst_page
);
260 while ((len
-= l
) != 0) {
261 l
= min_t(int, len
, PAGE_SIZE
);
262 memmove(kmap(*++dst_page
),
263 kmap(*++src_page
), l
);
265 set_page_dirty(*dst_page
);
269 void *src_ptr
, *dst_ptr
;
272 src_ptr
= kmap(*src_page
) + src
;
273 dst_ptr
= kmap(*dst_page
) + dst
;
274 if (PAGE_SIZE
- src
<
285 memmove(dst_ptr
, src_ptr
, l
);
287 set_page_dirty(*dst_page
);
293 } while ((len
-= l
));
298 void hfs_bnode_dump(struct hfs_bnode
*node
)
300 struct hfs_bnode_desc desc
;
304 hfs_dbg(BNODE_MOD
, "bnode: %d\n", node
->this);
305 hfs_bnode_read(node
, &desc
, 0, sizeof(desc
));
306 hfs_dbg(BNODE_MOD
, "%d, %d, %d, %d, %d\n",
307 be32_to_cpu(desc
.next
), be32_to_cpu(desc
.prev
),
308 desc
.type
, desc
.height
, be16_to_cpu(desc
.num_recs
));
310 off
= node
->tree
->node_size
- 2;
311 for (i
= be16_to_cpu(desc
.num_recs
); i
>= 0; off
-= 2, i
--) {
312 key_off
= hfs_bnode_read_u16(node
, off
);
313 hfs_dbg(BNODE_MOD
, " %d", key_off
);
314 if (i
&& node
->type
== HFS_NODE_INDEX
) {
317 if (node
->tree
->attributes
& HFS_TREE_VARIDXKEYS
||
318 node
->tree
->cnid
== HFSPLUS_ATTR_CNID
)
319 tmp
= hfs_bnode_read_u16(node
, key_off
) + 2;
321 tmp
= node
->tree
->max_key_len
+ 2;
322 hfs_dbg_cont(BNODE_MOD
, " (%d", tmp
);
323 hfs_bnode_read(node
, &cnid
, key_off
+ tmp
, 4);
324 hfs_dbg_cont(BNODE_MOD
, ",%d)", be32_to_cpu(cnid
));
325 } else if (i
&& node
->type
== HFS_NODE_LEAF
) {
328 tmp
= hfs_bnode_read_u16(node
, key_off
);
329 hfs_dbg_cont(BNODE_MOD
, " (%d)", tmp
);
332 hfs_dbg_cont(BNODE_MOD
, "\n");
335 void hfs_bnode_unlink(struct hfs_bnode
*node
)
337 struct hfs_btree
*tree
;
338 struct hfs_bnode
*tmp
;
343 tmp
= hfs_bnode_find(tree
, node
->prev
);
346 tmp
->next
= node
->next
;
347 cnid
= cpu_to_be32(tmp
->next
);
348 hfs_bnode_write(tmp
, &cnid
,
349 offsetof(struct hfs_bnode_desc
, next
), 4);
351 } else if (node
->type
== HFS_NODE_LEAF
)
352 tree
->leaf_head
= node
->next
;
355 tmp
= hfs_bnode_find(tree
, node
->next
);
358 tmp
->prev
= node
->prev
;
359 cnid
= cpu_to_be32(tmp
->prev
);
360 hfs_bnode_write(tmp
, &cnid
,
361 offsetof(struct hfs_bnode_desc
, prev
), 4);
363 } else if (node
->type
== HFS_NODE_LEAF
)
364 tree
->leaf_tail
= node
->prev
;
367 if (!node
->prev
&& !node
->next
)
368 hfs_dbg(BNODE_MOD
, "hfs_btree_del_level\n");
373 set_bit(HFS_BNODE_DELETED
, &node
->flags
);
376 static inline int hfs_bnode_hash(u32 num
)
378 num
= (num
>> 16) + num
;
380 return num
& (NODE_HASH_SIZE
- 1);
383 struct hfs_bnode
*hfs_bnode_findhash(struct hfs_btree
*tree
, u32 cnid
)
385 struct hfs_bnode
*node
;
387 if (cnid
>= tree
->node_count
) {
388 pr_err("request for non-existent node %d in B*Tree\n",
393 for (node
= tree
->node_hash
[hfs_bnode_hash(cnid
)];
394 node
; node
= node
->next_hash
)
395 if (node
->this == cnid
)
400 static struct hfs_bnode
*__hfs_bnode_create(struct hfs_btree
*tree
, u32 cnid
)
402 struct hfs_bnode
*node
, *node2
;
403 struct address_space
*mapping
;
405 int size
, block
, i
, hash
;
408 if (cnid
>= tree
->node_count
) {
409 pr_err("request for non-existent node %d in B*Tree\n",
414 size
= sizeof(struct hfs_bnode
) + tree
->pages_per_bnode
*
415 sizeof(struct page
*);
416 node
= kzalloc(size
, GFP_KERNEL
);
421 set_bit(HFS_BNODE_NEW
, &node
->flags
);
422 atomic_set(&node
->refcnt
, 1);
423 hfs_dbg(BNODE_REFS
, "new_node(%d:%d): 1\n",
424 node
->tree
->cnid
, node
->this);
425 init_waitqueue_head(&node
->lock_wq
);
426 spin_lock(&tree
->hash_lock
);
427 node2
= hfs_bnode_findhash(tree
, cnid
);
429 hash
= hfs_bnode_hash(cnid
);
430 node
->next_hash
= tree
->node_hash
[hash
];
431 tree
->node_hash
[hash
] = node
;
432 tree
->node_hash_cnt
++;
434 spin_unlock(&tree
->hash_lock
);
436 wait_event(node2
->lock_wq
,
437 !test_bit(HFS_BNODE_NEW
, &node2
->flags
));
440 spin_unlock(&tree
->hash_lock
);
442 mapping
= tree
->inode
->i_mapping
;
443 off
= (loff_t
)cnid
<< tree
->node_size_shift
;
444 block
= off
>> PAGE_SHIFT
;
445 node
->page_offset
= off
& ~PAGE_MASK
;
446 for (i
= 0; i
< tree
->pages_per_bnode
; block
++, i
++) {
447 page
= read_mapping_page(mapping
, block
, NULL
);
450 if (PageError(page
)) {
454 node
->page
[i
] = page
;
459 set_bit(HFS_BNODE_ERROR
, &node
->flags
);
463 void hfs_bnode_unhash(struct hfs_bnode
*node
)
465 struct hfs_bnode
**p
;
467 hfs_dbg(BNODE_REFS
, "remove_node(%d:%d): %d\n",
468 node
->tree
->cnid
, node
->this, atomic_read(&node
->refcnt
));
469 for (p
= &node
->tree
->node_hash
[hfs_bnode_hash(node
->this)];
470 *p
&& *p
!= node
; p
= &(*p
)->next_hash
)
473 *p
= node
->next_hash
;
474 node
->tree
->node_hash_cnt
--;
477 /* Load a particular node out of a tree */
478 struct hfs_bnode
*hfs_bnode_find(struct hfs_btree
*tree
, u32 num
)
480 struct hfs_bnode
*node
;
481 struct hfs_bnode_desc
*desc
;
482 int i
, rec_off
, off
, next_off
;
483 int entry_size
, key_size
;
485 spin_lock(&tree
->hash_lock
);
486 node
= hfs_bnode_findhash(tree
, num
);
489 spin_unlock(&tree
->hash_lock
);
490 wait_event(node
->lock_wq
,
491 !test_bit(HFS_BNODE_NEW
, &node
->flags
));
492 if (test_bit(HFS_BNODE_ERROR
, &node
->flags
))
496 spin_unlock(&tree
->hash_lock
);
497 node
= __hfs_bnode_create(tree
, num
);
499 return ERR_PTR(-ENOMEM
);
500 if (test_bit(HFS_BNODE_ERROR
, &node
->flags
))
502 if (!test_bit(HFS_BNODE_NEW
, &node
->flags
))
505 desc
= (struct hfs_bnode_desc
*)(kmap(node
->page
[0]) +
507 node
->prev
= be32_to_cpu(desc
->prev
);
508 node
->next
= be32_to_cpu(desc
->next
);
509 node
->num_recs
= be16_to_cpu(desc
->num_recs
);
510 node
->type
= desc
->type
;
511 node
->height
= desc
->height
;
512 kunmap(node
->page
[0]);
514 switch (node
->type
) {
515 case HFS_NODE_HEADER
:
517 if (node
->height
!= 0)
521 if (node
->height
!= 1)
525 if (node
->height
<= 1 || node
->height
> tree
->depth
)
532 rec_off
= tree
->node_size
- 2;
533 off
= hfs_bnode_read_u16(node
, rec_off
);
534 if (off
!= sizeof(struct hfs_bnode_desc
))
536 for (i
= 1; i
<= node
->num_recs
; off
= next_off
, i
++) {
538 next_off
= hfs_bnode_read_u16(node
, rec_off
);
539 if (next_off
<= off
||
540 next_off
> tree
->node_size
||
543 entry_size
= next_off
- off
;
544 if (node
->type
!= HFS_NODE_INDEX
&&
545 node
->type
!= HFS_NODE_LEAF
)
547 key_size
= hfs_bnode_read_u16(node
, off
) + 2;
548 if (key_size
>= entry_size
|| key_size
& 1)
551 clear_bit(HFS_BNODE_NEW
, &node
->flags
);
552 wake_up(&node
->lock_wq
);
556 set_bit(HFS_BNODE_ERROR
, &node
->flags
);
557 clear_bit(HFS_BNODE_NEW
, &node
->flags
);
558 wake_up(&node
->lock_wq
);
560 return ERR_PTR(-EIO
);
563 void hfs_bnode_free(struct hfs_bnode
*node
)
567 for (i
= 0; i
< node
->tree
->pages_per_bnode
; i
++)
569 put_page(node
->page
[i
]);
573 struct hfs_bnode
*hfs_bnode_create(struct hfs_btree
*tree
, u32 num
)
575 struct hfs_bnode
*node
;
579 spin_lock(&tree
->hash_lock
);
580 node
= hfs_bnode_findhash(tree
, num
);
581 spin_unlock(&tree
->hash_lock
);
583 pr_crit("new node %u already hashed?\n", num
);
587 node
= __hfs_bnode_create(tree
, num
);
589 return ERR_PTR(-ENOMEM
);
590 if (test_bit(HFS_BNODE_ERROR
, &node
->flags
)) {
592 return ERR_PTR(-EIO
);
596 memset(kmap(*pagep
) + node
->page_offset
, 0,
597 min_t(int, PAGE_SIZE
, tree
->node_size
));
598 set_page_dirty(*pagep
);
600 for (i
= 1; i
< tree
->pages_per_bnode
; i
++) {
601 memset(kmap(*++pagep
), 0, PAGE_SIZE
);
602 set_page_dirty(*pagep
);
605 clear_bit(HFS_BNODE_NEW
, &node
->flags
);
606 wake_up(&node
->lock_wq
);
611 void hfs_bnode_get(struct hfs_bnode
*node
)
614 atomic_inc(&node
->refcnt
);
615 hfs_dbg(BNODE_REFS
, "get_node(%d:%d): %d\n",
616 node
->tree
->cnid
, node
->this,
617 atomic_read(&node
->refcnt
));
621 /* Dispose of resources used by a node */
622 void hfs_bnode_put(struct hfs_bnode
*node
)
625 struct hfs_btree
*tree
= node
->tree
;
628 hfs_dbg(BNODE_REFS
, "put_node(%d:%d): %d\n",
629 node
->tree
->cnid
, node
->this,
630 atomic_read(&node
->refcnt
));
631 BUG_ON(!atomic_read(&node
->refcnt
));
632 if (!atomic_dec_and_lock(&node
->refcnt
, &tree
->hash_lock
))
634 for (i
= 0; i
< tree
->pages_per_bnode
; i
++) {
637 mark_page_accessed(node
->page
[i
]);
640 if (test_bit(HFS_BNODE_DELETED
, &node
->flags
)) {
641 hfs_bnode_unhash(node
);
642 spin_unlock(&tree
->hash_lock
);
643 if (hfs_bnode_need_zeroout(tree
))
644 hfs_bnode_clear(node
, 0, tree
->node_size
);
646 hfs_bnode_free(node
);
649 spin_unlock(&tree
->hash_lock
);
654 * Unused nodes have to be zeroed if this is the catalog tree and
655 * a corresponding flag in the volume header is set.
657 bool hfs_bnode_need_zeroout(struct hfs_btree
*tree
)
659 struct super_block
*sb
= tree
->inode
->i_sb
;
660 struct hfsplus_sb_info
*sbi
= HFSPLUS_SB(sb
);
661 const u32 volume_attr
= be32_to_cpu(sbi
->s_vhdr
->attributes
);
663 return tree
->cnid
== HFSPLUS_CAT_CNID
&&
664 volume_attr
& HFSPLUS_VOL_UNUSED_NODE_FIX
;