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"
24 static struct btrfs_dir_item
*btrfs_match_dir_item_name(struct btrfs_root
*root
,
25 struct btrfs_path
*path
,
26 const char *name
, int name_len
);
29 * insert a name into a directory, doing overflow properly if there is a hash
30 * collision. data_size indicates how big the item inserted should be. On
31 * success a struct btrfs_dir_item pointer is returned, otherwise it is
34 * The name is not copied into the dir item, you have to do that yourself.
36 static struct btrfs_dir_item
*insert_with_overflow(struct btrfs_trans_handle
38 struct btrfs_root
*root
,
39 struct btrfs_path
*path
,
40 struct btrfs_key
*cpu_key
,
47 struct btrfs_item
*item
;
48 struct extent_buffer
*leaf
;
50 ret
= btrfs_insert_empty_item(trans
, root
, path
, cpu_key
, data_size
);
52 struct btrfs_dir_item
*di
;
53 di
= btrfs_match_dir_item_name(root
, path
, name
, name_len
);
55 return ERR_PTR(-EEXIST
);
56 btrfs_extend_item(root
, path
, data_size
);
60 leaf
= path
->nodes
[0];
61 item
= btrfs_item_nr(leaf
, path
->slots
[0]);
62 ptr
= btrfs_item_ptr(leaf
, path
->slots
[0], char);
63 BUG_ON(data_size
> btrfs_item_size(leaf
, item
));
64 ptr
+= btrfs_item_size(leaf
, item
) - data_size
;
65 return (struct btrfs_dir_item
*)ptr
;
69 * xattrs work a lot like directories, this inserts an xattr item
72 int btrfs_insert_xattr_item(struct btrfs_trans_handle
*trans
,
73 struct btrfs_root
*root
,
74 struct btrfs_path
*path
, u64 objectid
,
75 const char *name
, u16 name_len
,
76 const void *data
, u16 data_len
)
79 struct btrfs_dir_item
*dir_item
;
80 unsigned long name_ptr
, data_ptr
;
81 struct btrfs_key key
, location
;
82 struct btrfs_disk_key disk_key
;
83 struct extent_buffer
*leaf
;
86 BUG_ON(name_len
+ data_len
> BTRFS_MAX_XATTR_SIZE(root
));
88 key
.objectid
= objectid
;
89 btrfs_set_key_type(&key
, BTRFS_XATTR_ITEM_KEY
);
90 key
.offset
= btrfs_name_hash(name
, name_len
);
92 data_size
= sizeof(*dir_item
) + name_len
+ data_len
;
93 dir_item
= insert_with_overflow(trans
, root
, path
, &key
, data_size
,
96 return PTR_ERR(dir_item
);
97 memset(&location
, 0, sizeof(location
));
99 leaf
= path
->nodes
[0];
100 btrfs_cpu_key_to_disk(&disk_key
, &location
);
101 btrfs_set_dir_item_key(leaf
, dir_item
, &disk_key
);
102 btrfs_set_dir_type(leaf
, dir_item
, BTRFS_FT_XATTR
);
103 btrfs_set_dir_name_len(leaf
, dir_item
, name_len
);
104 btrfs_set_dir_transid(leaf
, dir_item
, trans
->transid
);
105 btrfs_set_dir_data_len(leaf
, dir_item
, data_len
);
106 name_ptr
= (unsigned long)(dir_item
+ 1);
107 data_ptr
= (unsigned long)((char *)name_ptr
+ name_len
);
109 write_extent_buffer(leaf
, name
, name_ptr
, name_len
);
110 write_extent_buffer(leaf
, data
, data_ptr
, data_len
);
111 btrfs_mark_buffer_dirty(path
->nodes
[0]);
117 * insert a directory item in the tree, doing all the magic for
118 * both indexes. 'dir' indicates which objectid to insert it into,
119 * 'location' is the key to stuff into the directory item, 'type' is the
120 * type of the inode we're pointing to, and 'index' is the sequence number
121 * to use for the second index (if one is created).
122 * Will return 0 or -ENOMEM
124 int btrfs_insert_dir_item(struct btrfs_trans_handle
*trans
, struct btrfs_root
125 *root
, const char *name
, int name_len
,
126 struct inode
*dir
, struct btrfs_key
*location
,
131 struct btrfs_path
*path
;
132 struct btrfs_dir_item
*dir_item
;
133 struct extent_buffer
*leaf
;
134 unsigned long name_ptr
;
135 struct btrfs_key key
;
136 struct btrfs_disk_key disk_key
;
139 key
.objectid
= btrfs_ino(dir
);
140 btrfs_set_key_type(&key
, BTRFS_DIR_ITEM_KEY
);
141 key
.offset
= btrfs_name_hash(name
, name_len
);
143 path
= btrfs_alloc_path();
146 path
->leave_spinning
= 1;
148 btrfs_cpu_key_to_disk(&disk_key
, location
);
150 data_size
= sizeof(*dir_item
) + name_len
;
151 dir_item
= insert_with_overflow(trans
, root
, path
, &key
, data_size
,
153 if (IS_ERR(dir_item
)) {
154 ret
= PTR_ERR(dir_item
);
160 leaf
= path
->nodes
[0];
161 btrfs_set_dir_item_key(leaf
, dir_item
, &disk_key
);
162 btrfs_set_dir_type(leaf
, dir_item
, type
);
163 btrfs_set_dir_data_len(leaf
, dir_item
, 0);
164 btrfs_set_dir_name_len(leaf
, dir_item
, name_len
);
165 btrfs_set_dir_transid(leaf
, dir_item
, trans
->transid
);
166 name_ptr
= (unsigned long)(dir_item
+ 1);
168 write_extent_buffer(leaf
, name
, name_ptr
, name_len
);
169 btrfs_mark_buffer_dirty(leaf
);
172 /* FIXME, use some real flag for selecting the extra index */
173 if (root
== root
->fs_info
->tree_root
) {
177 btrfs_release_path(path
);
179 ret2
= btrfs_insert_delayed_dir_index(trans
, root
, name
, name_len
, dir
,
180 &disk_key
, type
, index
);
182 btrfs_free_path(path
);
191 * lookup a directory item based on name. 'dir' is the objectid
192 * we're searching in, and 'mod' tells us if you plan on deleting the
193 * item (use mod < 0) or changing the options (use mod > 0)
195 struct btrfs_dir_item
*btrfs_lookup_dir_item(struct btrfs_trans_handle
*trans
,
196 struct btrfs_root
*root
,
197 struct btrfs_path
*path
, u64 dir
,
198 const char *name
, int name_len
,
202 struct btrfs_key key
;
203 int ins_len
= mod
< 0 ? -1 : 0;
207 btrfs_set_key_type(&key
, BTRFS_DIR_ITEM_KEY
);
209 key
.offset
= btrfs_name_hash(name
, name_len
);
211 ret
= btrfs_search_slot(trans
, root
, &key
, path
, ins_len
, cow
);
217 return btrfs_match_dir_item_name(root
, path
, name
, name_len
);
220 int btrfs_check_dir_item_collision(struct btrfs_root
*root
, u64 dir
,
221 const char *name
, int name_len
)
224 struct btrfs_key key
;
225 struct btrfs_dir_item
*di
;
227 struct extent_buffer
*leaf
;
229 struct btrfs_path
*path
;
232 path
= btrfs_alloc_path();
237 btrfs_set_key_type(&key
, BTRFS_DIR_ITEM_KEY
);
238 key
.offset
= btrfs_name_hash(name
, name_len
);
240 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
242 /* return back any errors */
246 /* nothing found, we're safe */
252 /* we found an item, look for our name in the item */
253 di
= btrfs_match_dir_item_name(root
, path
, name
, name_len
);
255 /* our exact name was found */
261 * see if there is room in the item to insert this
264 data_size
= sizeof(*di
) + name_len
+ sizeof(struct btrfs_item
);
265 leaf
= path
->nodes
[0];
266 slot
= path
->slots
[0];
267 if (data_size
+ btrfs_item_size_nr(leaf
, slot
) +
268 sizeof(struct btrfs_item
) > BTRFS_LEAF_DATA_SIZE(root
)) {
271 /* plenty of insertion room */
275 btrfs_free_path(path
);
280 * lookup a directory item based on index. 'dir' is the objectid
281 * we're searching in, and 'mod' tells us if you plan on deleting the
282 * item (use mod < 0) or changing the options (use mod > 0)
284 * The name is used to make sure the index really points to the name you were
287 struct btrfs_dir_item
*
288 btrfs_lookup_dir_index_item(struct btrfs_trans_handle
*trans
,
289 struct btrfs_root
*root
,
290 struct btrfs_path
*path
, u64 dir
,
291 u64 objectid
, const char *name
, int name_len
,
295 struct btrfs_key key
;
296 int ins_len
= mod
< 0 ? -1 : 0;
300 btrfs_set_key_type(&key
, BTRFS_DIR_INDEX_KEY
);
301 key
.offset
= objectid
;
303 ret
= btrfs_search_slot(trans
, root
, &key
, path
, ins_len
, cow
);
307 return ERR_PTR(-ENOENT
);
308 return btrfs_match_dir_item_name(root
, path
, name
, name_len
);
311 struct btrfs_dir_item
*
312 btrfs_search_dir_index_item(struct btrfs_root
*root
,
313 struct btrfs_path
*path
, u64 dirid
,
314 const char *name
, int name_len
)
316 struct extent_buffer
*leaf
;
317 struct btrfs_dir_item
*di
;
318 struct btrfs_key key
;
322 key
.objectid
= dirid
;
323 key
.type
= BTRFS_DIR_INDEX_KEY
;
326 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
330 leaf
= path
->nodes
[0];
331 nritems
= btrfs_header_nritems(leaf
);
334 if (path
->slots
[0] >= nritems
) {
335 ret
= btrfs_next_leaf(root
, path
);
340 leaf
= path
->nodes
[0];
341 nritems
= btrfs_header_nritems(leaf
);
345 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
346 if (key
.objectid
!= dirid
|| key
.type
!= BTRFS_DIR_INDEX_KEY
)
349 di
= btrfs_match_dir_item_name(root
, path
, name
, name_len
);
358 struct btrfs_dir_item
*btrfs_lookup_xattr(struct btrfs_trans_handle
*trans
,
359 struct btrfs_root
*root
,
360 struct btrfs_path
*path
, u64 dir
,
361 const char *name
, u16 name_len
,
365 struct btrfs_key key
;
366 int ins_len
= mod
< 0 ? -1 : 0;
370 btrfs_set_key_type(&key
, BTRFS_XATTR_ITEM_KEY
);
371 key
.offset
= btrfs_name_hash(name
, name_len
);
372 ret
= btrfs_search_slot(trans
, root
, &key
, path
, ins_len
, cow
);
378 return btrfs_match_dir_item_name(root
, path
, name
, name_len
);
382 * helper function to look at the directory item pointed to by 'path'
383 * this walks through all the entries in a dir item and finds one
384 * for a specific name.
386 static struct btrfs_dir_item
*btrfs_match_dir_item_name(struct btrfs_root
*root
,
387 struct btrfs_path
*path
,
388 const char *name
, int name_len
)
390 struct btrfs_dir_item
*dir_item
;
391 unsigned long name_ptr
;
395 struct extent_buffer
*leaf
;
397 leaf
= path
->nodes
[0];
398 dir_item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_dir_item
);
399 if (verify_dir_item(root
, leaf
, dir_item
))
402 total_len
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
403 while (cur
< total_len
) {
404 this_len
= sizeof(*dir_item
) +
405 btrfs_dir_name_len(leaf
, dir_item
) +
406 btrfs_dir_data_len(leaf
, dir_item
);
407 name_ptr
= (unsigned long)(dir_item
+ 1);
409 if (btrfs_dir_name_len(leaf
, dir_item
) == name_len
&&
410 memcmp_extent_buffer(leaf
, name
, name_ptr
, name_len
) == 0)
414 dir_item
= (struct btrfs_dir_item
*)((char *)dir_item
+
421 * given a pointer into a directory item, delete it. This
422 * handles items that have more than one entry in them.
424 int btrfs_delete_one_dir_name(struct btrfs_trans_handle
*trans
,
425 struct btrfs_root
*root
,
426 struct btrfs_path
*path
,
427 struct btrfs_dir_item
*di
)
430 struct extent_buffer
*leaf
;
435 leaf
= path
->nodes
[0];
436 sub_item_len
= sizeof(*di
) + btrfs_dir_name_len(leaf
, di
) +
437 btrfs_dir_data_len(leaf
, di
);
438 item_len
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
439 if (sub_item_len
== item_len
) {
440 ret
= btrfs_del_item(trans
, root
, path
);
443 unsigned long ptr
= (unsigned long)di
;
446 start
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
447 memmove_extent_buffer(leaf
, ptr
, ptr
+ sub_item_len
,
448 item_len
- (ptr
+ sub_item_len
- start
));
449 btrfs_truncate_item(root
, path
, item_len
- sub_item_len
, 1);
454 int verify_dir_item(struct btrfs_root
*root
,
455 struct extent_buffer
*leaf
,
456 struct btrfs_dir_item
*dir_item
)
458 u16 namelen
= BTRFS_NAME_LEN
;
459 u8 type
= btrfs_dir_type(leaf
, dir_item
);
461 if (type
>= BTRFS_FT_MAX
) {
462 printk(KERN_CRIT
"btrfs: invalid dir item type: %d\n",
467 if (type
== BTRFS_FT_XATTR
)
468 namelen
= XATTR_NAME_MAX
;
470 if (btrfs_dir_name_len(leaf
, dir_item
) > namelen
) {
471 printk(KERN_CRIT
"btrfs: invalid dir item name len: %u\n",
472 (unsigned)btrfs_dir_data_len(leaf
, dir_item
));
476 /* BTRFS_MAX_XATTR_SIZE is the same for all dir items */
477 if (btrfs_dir_data_len(leaf
, dir_item
) > BTRFS_MAX_XATTR_SIZE(root
)) {
478 printk(KERN_CRIT
"btrfs: invalid dir item data len: %u\n",
479 (unsigned)btrfs_dir_data_len(leaf
, dir_item
));