2 * linux/fs/hfsplus/btree.c
5 * Brad Boyer (flar@allandria.com)
6 * (C) 2003 Ardis Technologies <roman@ardistech.com>
8 * Handle opening/closing btree
11 #include <linux/slab.h>
12 #include <linux/pagemap.h>
13 #include <linux/log2.h>
15 #include "hfsplus_fs.h"
16 #include "hfsplus_raw.h"
19 /* Get a reference to a B*Tree and do some initial checks */
20 struct hfs_btree *hfs_btree_open(struct super_block *sb, u32 id)
22 struct hfs_btree *tree;
23 struct hfs_btree_header_rec *head;
24 struct address_space *mapping;
29 tree = kzalloc(sizeof(*tree), GFP_KERNEL);
33 mutex_init(&tree->tree_lock);
34 spin_lock_init(&tree->hash_lock);
37 inode = hfsplus_iget(sb, id);
42 if (!HFSPLUS_I(tree->inode)->first_blocks) {
44 "hfs: invalid btree extent records (0 size).\n");
48 mapping = tree->inode->i_mapping;
49 page = read_mapping_page(mapping, 0, NULL);
54 head = (struct hfs_btree_header_rec *)(kmap(page) + sizeof(struct hfs_bnode_desc));
55 tree->root = be32_to_cpu(head->root);
56 tree->leaf_count = be32_to_cpu(head->leaf_count);
57 tree->leaf_head = be32_to_cpu(head->leaf_head);
58 tree->leaf_tail = be32_to_cpu(head->leaf_tail);
59 tree->node_count = be32_to_cpu(head->node_count);
60 tree->free_nodes = be32_to_cpu(head->free_nodes);
61 tree->attributes = be32_to_cpu(head->attributes);
62 tree->node_size = be16_to_cpu(head->node_size);
63 tree->max_key_len = be16_to_cpu(head->max_key_len);
64 tree->depth = be16_to_cpu(head->depth);
66 /* Verify the tree and set the correct compare function */
68 case HFSPLUS_EXT_CNID:
69 if (tree->max_key_len != HFSPLUS_EXT_KEYLEN - sizeof(u16)) {
70 printk(KERN_ERR "hfs: invalid extent max_key_len %d\n",
74 if (tree->attributes & HFS_TREE_VARIDXKEYS) {
75 printk(KERN_ERR "hfs: invalid extent btree flag\n");
79 tree->keycmp = hfsplus_ext_cmp_key;
81 case HFSPLUS_CAT_CNID:
82 if (tree->max_key_len != HFSPLUS_CAT_KEYLEN - sizeof(u16)) {
83 printk(KERN_ERR "hfs: invalid catalog max_key_len %d\n",
87 if (!(tree->attributes & HFS_TREE_VARIDXKEYS)) {
88 printk(KERN_ERR "hfs: invalid catalog btree flag\n");
92 if (test_bit(HFSPLUS_SB_HFSX, &HFSPLUS_SB(sb)->flags) &&
93 (head->key_type == HFSPLUS_KEY_BINARY))
94 tree->keycmp = hfsplus_cat_bin_cmp_key;
96 tree->keycmp = hfsplus_cat_case_cmp_key;
97 set_bit(HFSPLUS_SB_CASEFOLD, &HFSPLUS_SB(sb)->flags);
101 printk(KERN_ERR "hfs: unknown B*Tree requested\n");
105 if (!(tree->attributes & HFS_TREE_BIGKEYS)) {
106 printk(KERN_ERR "hfs: invalid btree flag\n");
110 size = tree->node_size;
111 if (!is_power_of_2(size))
113 if (!tree->node_count)
116 tree->node_size_shift = ffs(size) - 1;
118 tree->pages_per_bnode = (tree->node_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
121 page_cache_release(page);
125 page_cache_release(page);
127 tree->inode->i_mapping->a_ops = &hfsplus_aops;
134 /* Release resources used by a btree */
135 void hfs_btree_close(struct hfs_btree *tree)
137 struct hfs_bnode *node;
143 for (i = 0; i < NODE_HASH_SIZE; i++) {
144 while ((node = tree->node_hash[i])) {
145 tree->node_hash[i] = node->next_hash;
146 if (atomic_read(&node->refcnt))
147 printk(KERN_CRIT "hfs: node %d:%d still has %d user(s)!\n",
148 node->tree->cnid, node->this, atomic_read(&node->refcnt));
149 hfs_bnode_free(node);
150 tree->node_hash_cnt--;
157 void hfs_btree_write(struct hfs_btree *tree)
159 struct hfs_btree_header_rec *head;
160 struct hfs_bnode *node;
163 node = hfs_bnode_find(tree, 0);
167 /* Load the header */
168 page = node->page[0];
169 head = (struct hfs_btree_header_rec *)(kmap(page) + sizeof(struct hfs_bnode_desc));
171 head->root = cpu_to_be32(tree->root);
172 head->leaf_count = cpu_to_be32(tree->leaf_count);
173 head->leaf_head = cpu_to_be32(tree->leaf_head);
174 head->leaf_tail = cpu_to_be32(tree->leaf_tail);
175 head->node_count = cpu_to_be32(tree->node_count);
176 head->free_nodes = cpu_to_be32(tree->free_nodes);
177 head->attributes = cpu_to_be32(tree->attributes);
178 head->depth = cpu_to_be16(tree->depth);
181 set_page_dirty(page);
185 static struct hfs_bnode *hfs_bmap_new_bmap(struct hfs_bnode *prev, u32 idx)
187 struct hfs_btree *tree = prev->tree;
188 struct hfs_bnode *node;
189 struct hfs_bnode_desc desc;
192 node = hfs_bnode_create(tree, idx);
198 cnid = cpu_to_be32(idx);
199 hfs_bnode_write(prev, &cnid, offsetof(struct hfs_bnode_desc, next), 4);
201 node->type = HFS_NODE_MAP;
203 hfs_bnode_clear(node, 0, tree->node_size);
206 desc.type = HFS_NODE_MAP;
208 desc.num_recs = cpu_to_be16(1);
210 hfs_bnode_write(node, &desc, 0, sizeof(desc));
211 hfs_bnode_write_u16(node, 14, 0x8000);
212 hfs_bnode_write_u16(node, tree->node_size - 2, 14);
213 hfs_bnode_write_u16(node, tree->node_size - 4, tree->node_size - 6);
218 struct hfs_bnode *hfs_bmap_alloc(struct hfs_btree *tree)
220 struct hfs_bnode *node, *next_node;
229 while (!tree->free_nodes) {
230 struct inode *inode = tree->inode;
231 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
235 res = hfsplus_file_extend(inode);
238 hip->phys_size = inode->i_size =
239 (loff_t)hip->alloc_blocks <<
240 HFSPLUS_SB(tree->sb)->alloc_blksz_shift;
242 hip->alloc_blocks << HFSPLUS_SB(tree->sb)->fs_shift;
243 inode_set_bytes(inode, inode->i_size);
244 count = inode->i_size >> tree->node_size_shift;
245 tree->free_nodes = count - tree->node_count;
246 tree->node_count = count;
250 node = hfs_bnode_find(tree, nidx);
253 len = hfs_brec_lenoff(node, 2, &off16);
256 off += node->page_offset;
257 pagep = node->page + (off >> PAGE_CACHE_SHIFT);
259 off &= ~PAGE_CACHE_MASK;
266 for (m = 0x80, i = 0; i < 8; m >>= 1, i++) {
270 set_page_dirty(*pagep);
273 mark_inode_dirty(tree->inode);
275 return hfs_bnode_create(tree, idx);
279 if (++off >= PAGE_CACHE_SIZE) {
281 data = kmap(*++pagep);
290 printk(KERN_DEBUG "hfs: create new bmap node...\n");
291 next_node = hfs_bmap_new_bmap(node, idx);
293 next_node = hfs_bnode_find(tree, nidx);
295 if (IS_ERR(next_node))
299 len = hfs_brec_lenoff(node, 0, &off16);
301 off += node->page_offset;
302 pagep = node->page + (off >> PAGE_CACHE_SHIFT);
304 off &= ~PAGE_CACHE_MASK;
308 void hfs_bmap_free(struct hfs_bnode *node)
310 struct hfs_btree *tree;
316 dprint(DBG_BNODE_MOD, "btree_free_node: %u\n", node->this);
320 node = hfs_bnode_find(tree, 0);
323 len = hfs_brec_lenoff(node, 2, &off);
324 while (nidx >= len * 8) {
332 printk(KERN_CRIT "hfs: unable to free bnode %u. bmap not found!\n", node->this);
335 node = hfs_bnode_find(tree, i);
338 if (node->type != HFS_NODE_MAP) {
340 printk(KERN_CRIT "hfs: invalid bmap found! (%u,%d)\n", node->this, node->type);
344 len = hfs_brec_lenoff(node, 0, &off);
346 off += node->page_offset + nidx / 8;
347 page = node->page[off >> PAGE_CACHE_SHIFT];
349 off &= ~PAGE_CACHE_MASK;
350 m = 1 << (~nidx & 7);
353 printk(KERN_CRIT "hfs: trying to free free bnode %u(%d)\n", node->this, node->type);
358 data[off] = byte & ~m;
359 set_page_dirty(page);
363 mark_inode_dirty(tree->inode);