2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
22 #include "transaction.h"
25 * insert a name into a directory, doing overflow properly if there is a hash
26 * collision. data_size indicates how big the item inserted should be. On
27 * success a struct btrfs_dir_item pointer is returned, otherwise it is
30 * The name is not copied into the dir item, you have to do that yourself.
32 static struct btrfs_dir_item *insert_with_overflow(struct btrfs_trans_handle
34 struct btrfs_root *root,
35 struct btrfs_path *path,
36 struct btrfs_key *cpu_key,
43 struct btrfs_item *item;
44 struct extent_buffer *leaf;
46 ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size);
48 struct btrfs_dir_item *di;
49 di = btrfs_match_dir_item_name(root, path, name, name_len);
51 return ERR_PTR(-EEXIST);
52 ret = btrfs_extend_item(trans, root, path, data_size);
57 leaf = path->nodes[0];
58 item = btrfs_item_nr(leaf, path->slots[0]);
59 ptr = btrfs_item_ptr(leaf, path->slots[0], char);
60 BUG_ON(data_size > btrfs_item_size(leaf, item));
61 ptr += btrfs_item_size(leaf, item) - data_size;
62 return (struct btrfs_dir_item *)ptr;
66 * xattrs work a lot like directories, this inserts an xattr item
69 int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans,
70 struct btrfs_root *root,
71 struct btrfs_path *path, u64 objectid,
72 const char *name, u16 name_len,
73 const void *data, u16 data_len)
76 struct btrfs_dir_item *dir_item;
77 unsigned long name_ptr, data_ptr;
78 struct btrfs_key key, location;
79 struct btrfs_disk_key disk_key;
80 struct extent_buffer *leaf;
83 BUG_ON(name_len + data_len > BTRFS_MAX_XATTR_SIZE(root));
85 key.objectid = objectid;
86 btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY);
87 key.offset = btrfs_name_hash(name, name_len);
89 data_size = sizeof(*dir_item) + name_len + data_len;
90 dir_item = insert_with_overflow(trans, root, path, &key, data_size,
93 return PTR_ERR(dir_item);
94 memset(&location, 0, sizeof(location));
96 leaf = path->nodes[0];
97 btrfs_cpu_key_to_disk(&disk_key, &location);
98 btrfs_set_dir_item_key(leaf, dir_item, &disk_key);
99 btrfs_set_dir_type(leaf, dir_item, BTRFS_FT_XATTR);
100 btrfs_set_dir_name_len(leaf, dir_item, name_len);
101 btrfs_set_dir_transid(leaf, dir_item, trans->transid);
102 btrfs_set_dir_data_len(leaf, dir_item, data_len);
103 name_ptr = (unsigned long)(dir_item + 1);
104 data_ptr = (unsigned long)((char *)name_ptr + name_len);
106 write_extent_buffer(leaf, name, name_ptr, name_len);
107 write_extent_buffer(leaf, data, data_ptr, data_len);
108 btrfs_mark_buffer_dirty(path->nodes[0]);
114 * insert a directory item in the tree, doing all the magic for
115 * both indexes. 'dir' indicates which objectid to insert it into,
116 * 'location' is the key to stuff into the directory item, 'type' is the
117 * type of the inode we're pointing to, and 'index' is the sequence number
118 * to use for the second index (if one is created).
120 int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
121 *root, const char *name, int name_len,
122 struct inode *dir, struct btrfs_key *location,
127 struct btrfs_path *path;
128 struct btrfs_dir_item *dir_item;
129 struct extent_buffer *leaf;
130 unsigned long name_ptr;
131 struct btrfs_key key;
132 struct btrfs_disk_key disk_key;
135 key.objectid = btrfs_ino(dir);
136 btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
137 key.offset = btrfs_name_hash(name, name_len);
139 path = btrfs_alloc_path();
142 path->leave_spinning = 1;
144 btrfs_cpu_key_to_disk(&disk_key, location);
146 data_size = sizeof(*dir_item) + name_len;
147 dir_item = insert_with_overflow(trans, root, path, &key, data_size,
149 if (IS_ERR(dir_item)) {
150 ret = PTR_ERR(dir_item);
156 leaf = path->nodes[0];
157 btrfs_set_dir_item_key(leaf, dir_item, &disk_key);
158 btrfs_set_dir_type(leaf, dir_item, type);
159 btrfs_set_dir_data_len(leaf, dir_item, 0);
160 btrfs_set_dir_name_len(leaf, dir_item, name_len);
161 btrfs_set_dir_transid(leaf, dir_item, trans->transid);
162 name_ptr = (unsigned long)(dir_item + 1);
164 write_extent_buffer(leaf, name, name_ptr, name_len);
165 btrfs_mark_buffer_dirty(leaf);
168 /* FIXME, use some real flag for selecting the extra index */
169 if (root == root->fs_info->tree_root) {
173 btrfs_release_path(path);
175 ret2 = btrfs_insert_delayed_dir_index(trans, root, name, name_len, dir,
176 &disk_key, type, index);
178 btrfs_free_path(path);
187 * lookup a directory item based on name. 'dir' is the objectid
188 * we're searching in, and 'mod' tells us if you plan on deleting the
189 * item (use mod < 0) or changing the options (use mod > 0)
191 struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
192 struct btrfs_root *root,
193 struct btrfs_path *path, u64 dir,
194 const char *name, int name_len,
198 struct btrfs_key key;
199 int ins_len = mod < 0 ? -1 : 0;
201 struct btrfs_key found_key;
202 struct extent_buffer *leaf;
205 btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
207 key.offset = btrfs_name_hash(name, name_len);
209 ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
213 if (path->slots[0] == 0)
218 leaf = path->nodes[0];
219 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
221 if (found_key.objectid != dir ||
222 btrfs_key_type(&found_key) != BTRFS_DIR_ITEM_KEY ||
223 found_key.offset != key.offset)
226 return btrfs_match_dir_item_name(root, path, name, name_len);
230 * lookup a directory item based on index. 'dir' is the objectid
231 * we're searching in, and 'mod' tells us if you plan on deleting the
232 * item (use mod < 0) or changing the options (use mod > 0)
234 * The name is used to make sure the index really points to the name you were
237 struct btrfs_dir_item *
238 btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
239 struct btrfs_root *root,
240 struct btrfs_path *path, u64 dir,
241 u64 objectid, const char *name, int name_len,
245 struct btrfs_key key;
246 int ins_len = mod < 0 ? -1 : 0;
250 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
251 key.offset = objectid;
253 ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
257 return ERR_PTR(-ENOENT);
258 return btrfs_match_dir_item_name(root, path, name, name_len);
261 struct btrfs_dir_item *
262 btrfs_search_dir_index_item(struct btrfs_root *root,
263 struct btrfs_path *path, u64 dirid,
264 const char *name, int name_len)
266 struct extent_buffer *leaf;
267 struct btrfs_dir_item *di;
268 struct btrfs_key key;
272 key.objectid = dirid;
273 key.type = BTRFS_DIR_INDEX_KEY;
276 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
280 leaf = path->nodes[0];
281 nritems = btrfs_header_nritems(leaf);
284 if (path->slots[0] >= nritems) {
285 ret = btrfs_next_leaf(root, path);
290 leaf = path->nodes[0];
291 nritems = btrfs_header_nritems(leaf);
295 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
296 if (key.objectid != dirid || key.type != BTRFS_DIR_INDEX_KEY)
299 di = btrfs_match_dir_item_name(root, path, name, name_len);
308 struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans,
309 struct btrfs_root *root,
310 struct btrfs_path *path, u64 dir,
311 const char *name, u16 name_len,
315 struct btrfs_key key;
316 int ins_len = mod < 0 ? -1 : 0;
318 struct btrfs_key found_key;
319 struct extent_buffer *leaf;
322 btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY);
323 key.offset = btrfs_name_hash(name, name_len);
324 ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
328 if (path->slots[0] == 0)
333 leaf = path->nodes[0];
334 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
336 if (found_key.objectid != dir ||
337 btrfs_key_type(&found_key) != BTRFS_XATTR_ITEM_KEY ||
338 found_key.offset != key.offset)
341 return btrfs_match_dir_item_name(root, path, name, name_len);
345 * helper function to look at the directory item pointed to by 'path'
346 * this walks through all the entries in a dir item and finds one
347 * for a specific name.
349 struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root,
350 struct btrfs_path *path,
351 const char *name, int name_len)
353 struct btrfs_dir_item *dir_item;
354 unsigned long name_ptr;
358 struct extent_buffer *leaf;
360 leaf = path->nodes[0];
361 dir_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item);
362 if (verify_dir_item(root, leaf, dir_item))
365 total_len = btrfs_item_size_nr(leaf, path->slots[0]);
366 while (cur < total_len) {
367 this_len = sizeof(*dir_item) +
368 btrfs_dir_name_len(leaf, dir_item) +
369 btrfs_dir_data_len(leaf, dir_item);
370 name_ptr = (unsigned long)(dir_item + 1);
372 if (btrfs_dir_name_len(leaf, dir_item) == name_len &&
373 memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0)
377 dir_item = (struct btrfs_dir_item *)((char *)dir_item +
384 * given a pointer into a directory item, delete it. This
385 * handles items that have more than one entry in them.
387 int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans,
388 struct btrfs_root *root,
389 struct btrfs_path *path,
390 struct btrfs_dir_item *di)
393 struct extent_buffer *leaf;
398 leaf = path->nodes[0];
399 sub_item_len = sizeof(*di) + btrfs_dir_name_len(leaf, di) +
400 btrfs_dir_data_len(leaf, di);
401 item_len = btrfs_item_size_nr(leaf, path->slots[0]);
402 if (sub_item_len == item_len) {
403 ret = btrfs_del_item(trans, root, path);
406 unsigned long ptr = (unsigned long)di;
409 start = btrfs_item_ptr_offset(leaf, path->slots[0]);
410 memmove_extent_buffer(leaf, ptr, ptr + sub_item_len,
411 item_len - (ptr + sub_item_len - start));
412 ret = btrfs_truncate_item(trans, root, path,
413 item_len - sub_item_len, 1);
418 int verify_dir_item(struct btrfs_root *root,
419 struct extent_buffer *leaf,
420 struct btrfs_dir_item *dir_item)
422 u16 namelen = BTRFS_NAME_LEN;
423 u8 type = btrfs_dir_type(leaf, dir_item);
425 if (type >= BTRFS_FT_MAX) {
426 printk(KERN_CRIT "btrfs: invalid dir item type: %d\n",
431 if (type == BTRFS_FT_XATTR)
432 namelen = XATTR_NAME_MAX;
434 if (btrfs_dir_name_len(leaf, dir_item) > namelen) {
435 printk(KERN_CRIT "btrfs: invalid dir item name len: %u\n",
436 (unsigned)btrfs_dir_data_len(leaf, dir_item));
440 /* BTRFS_MAX_XATTR_SIZE is the same for all dir items */
441 if (btrfs_dir_data_len(leaf, dir_item) > BTRFS_MAX_XATTR_SIZE(root)) {
442 printk(KERN_CRIT "btrfs: invalid dir item data len: %u\n",
443 (unsigned)btrfs_dir_data_len(leaf, dir_item));