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 * FIXME: at some point we should handle xattr's that are larger than
94 * what we can fit in our leaf. We set location to NULL b/c we arent
95 * pointing at anything else, that will change if we store the xattr
96 * data in a separate inode.
98 BUG_ON(IS_ERR(dir_item
));
99 memset(&location
, 0, sizeof(location
));
101 leaf
= path
->nodes
[0];
102 btrfs_cpu_key_to_disk(&disk_key
, &location
);
103 btrfs_set_dir_item_key(leaf
, dir_item
, &disk_key
);
104 btrfs_set_dir_type(leaf
, dir_item
, BTRFS_FT_XATTR
);
105 btrfs_set_dir_name_len(leaf
, dir_item
, name_len
);
106 btrfs_set_dir_transid(leaf
, dir_item
, trans
->transid
);
107 btrfs_set_dir_data_len(leaf
, dir_item
, data_len
);
108 name_ptr
= (unsigned long)(dir_item
+ 1);
109 data_ptr
= (unsigned long)((char *)name_ptr
+ name_len
);
111 write_extent_buffer(leaf
, name
, name_ptr
, name_len
);
112 write_extent_buffer(leaf
, data
, data_ptr
, data_len
);
113 btrfs_mark_buffer_dirty(path
->nodes
[0]);
119 * insert a directory item in the tree, doing all the magic for
120 * both indexes. 'dir' indicates which objectid to insert it into,
121 * 'location' is the key to stuff into the directory item, 'type' is the
122 * type of the inode we're pointing to, and 'index' is the sequence number
123 * to use for the second index (if one is created).
125 int btrfs_insert_dir_item(struct btrfs_trans_handle
*trans
, struct btrfs_root
126 *root
, const char *name
, int name_len
, u64 dir
,
127 struct btrfs_key
*location
, u8 type
, u64 index
)
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
;
140 btrfs_set_key_type(&key
, BTRFS_DIR_ITEM_KEY
);
141 key
.offset
= btrfs_name_hash(name
, name_len
);
143 path
= btrfs_alloc_path();
144 path
->leave_spinning
= 1;
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_cpu_key_to_disk(&disk_key
, location
);
158 btrfs_set_dir_item_key(leaf
, dir_item
, &disk_key
);
159 btrfs_set_dir_type(leaf
, dir_item
, type
);
160 btrfs_set_dir_data_len(leaf
, dir_item
, 0);
161 btrfs_set_dir_name_len(leaf
, dir_item
, name_len
);
162 btrfs_set_dir_transid(leaf
, dir_item
, trans
->transid
);
163 name_ptr
= (unsigned long)(dir_item
+ 1);
165 write_extent_buffer(leaf
, name
, name_ptr
, name_len
);
166 btrfs_mark_buffer_dirty(leaf
);
169 /* FIXME, use some real flag for selecting the extra index */
170 if (root
== root
->fs_info
->tree_root
) {
174 btrfs_release_path(root
, path
);
176 btrfs_set_key_type(&key
, BTRFS_DIR_INDEX_KEY
);
178 dir_item
= insert_with_overflow(trans
, root
, path
, &key
, data_size
,
180 if (IS_ERR(dir_item
)) {
181 ret2
= PTR_ERR(dir_item
);
184 leaf
= path
->nodes
[0];
185 btrfs_cpu_key_to_disk(&disk_key
, location
);
186 btrfs_set_dir_item_key(leaf
, dir_item
, &disk_key
);
187 btrfs_set_dir_type(leaf
, dir_item
, type
);
188 btrfs_set_dir_data_len(leaf
, dir_item
, 0);
189 btrfs_set_dir_name_len(leaf
, dir_item
, name_len
);
190 btrfs_set_dir_transid(leaf
, dir_item
, trans
->transid
);
191 name_ptr
= (unsigned long)(dir_item
+ 1);
192 write_extent_buffer(leaf
, name
, name_ptr
, name_len
);
193 btrfs_mark_buffer_dirty(leaf
);
197 btrfs_free_path(path
);
206 * lookup a directory item based on name. 'dir' is the objectid
207 * we're searching in, and 'mod' tells us if you plan on deleting the
208 * item (use mod < 0) or changing the options (use mod > 0)
210 struct btrfs_dir_item
*btrfs_lookup_dir_item(struct btrfs_trans_handle
*trans
,
211 struct btrfs_root
*root
,
212 struct btrfs_path
*path
, u64 dir
,
213 const char *name
, int name_len
,
217 struct btrfs_key key
;
218 int ins_len
= mod
< 0 ? -1 : 0;
220 struct btrfs_key found_key
;
221 struct extent_buffer
*leaf
;
224 btrfs_set_key_type(&key
, BTRFS_DIR_ITEM_KEY
);
226 key
.offset
= btrfs_name_hash(name
, name_len
);
228 ret
= btrfs_search_slot(trans
, root
, &key
, path
, ins_len
, cow
);
232 if (path
->slots
[0] == 0)
237 leaf
= path
->nodes
[0];
238 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
240 if (found_key
.objectid
!= dir
||
241 btrfs_key_type(&found_key
) != BTRFS_DIR_ITEM_KEY
||
242 found_key
.offset
!= key
.offset
)
245 return btrfs_match_dir_item_name(root
, path
, name
, name_len
);
249 * lookup a directory item based on index. 'dir' is the objectid
250 * we're searching in, and 'mod' tells us if you plan on deleting the
251 * item (use mod < 0) or changing the options (use mod > 0)
253 * The name is used to make sure the index really points to the name you were
256 struct btrfs_dir_item
*
257 btrfs_lookup_dir_index_item(struct btrfs_trans_handle
*trans
,
258 struct btrfs_root
*root
,
259 struct btrfs_path
*path
, u64 dir
,
260 u64 objectid
, const char *name
, int name_len
,
264 struct btrfs_key key
;
265 int ins_len
= mod
< 0 ? -1 : 0;
269 btrfs_set_key_type(&key
, BTRFS_DIR_INDEX_KEY
);
270 key
.offset
= objectid
;
272 ret
= btrfs_search_slot(trans
, root
, &key
, path
, ins_len
, cow
);
276 return ERR_PTR(-ENOENT
);
277 return btrfs_match_dir_item_name(root
, path
, name
, name_len
);
280 struct btrfs_dir_item
*
281 btrfs_search_dir_index_item(struct btrfs_root
*root
,
282 struct btrfs_path
*path
, u64 dirid
,
283 const char *name
, int name_len
)
285 struct extent_buffer
*leaf
;
286 struct btrfs_dir_item
*di
;
287 struct btrfs_key key
;
291 key
.objectid
= dirid
;
292 key
.type
= BTRFS_DIR_INDEX_KEY
;
295 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
299 leaf
= path
->nodes
[0];
300 nritems
= btrfs_header_nritems(leaf
);
303 if (path
->slots
[0] >= nritems
) {
304 ret
= btrfs_next_leaf(root
, path
);
309 leaf
= path
->nodes
[0];
310 nritems
= btrfs_header_nritems(leaf
);
314 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
315 if (key
.objectid
!= dirid
|| key
.type
!= BTRFS_DIR_INDEX_KEY
)
318 di
= btrfs_match_dir_item_name(root
, path
, name
, name_len
);
327 struct btrfs_dir_item
*btrfs_lookup_xattr(struct btrfs_trans_handle
*trans
,
328 struct btrfs_root
*root
,
329 struct btrfs_path
*path
, u64 dir
,
330 const char *name
, u16 name_len
,
334 struct btrfs_key key
;
335 int ins_len
= mod
< 0 ? -1 : 0;
337 struct btrfs_key found_key
;
338 struct extent_buffer
*leaf
;
341 btrfs_set_key_type(&key
, BTRFS_XATTR_ITEM_KEY
);
342 key
.offset
= btrfs_name_hash(name
, name_len
);
343 ret
= btrfs_search_slot(trans
, root
, &key
, path
, ins_len
, cow
);
347 if (path
->slots
[0] == 0)
352 leaf
= path
->nodes
[0];
353 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
355 if (found_key
.objectid
!= dir
||
356 btrfs_key_type(&found_key
) != BTRFS_XATTR_ITEM_KEY
||
357 found_key
.offset
!= key
.offset
)
360 return btrfs_match_dir_item_name(root
, path
, name
, name_len
);
364 * helper function to look at the directory item pointed to by 'path'
365 * this walks through all the entries in a dir item and finds one
366 * for a specific name.
368 struct btrfs_dir_item
*btrfs_match_dir_item_name(struct btrfs_root
*root
,
369 struct btrfs_path
*path
,
370 const char *name
, int name_len
)
372 struct btrfs_dir_item
*dir_item
;
373 unsigned long name_ptr
;
377 struct extent_buffer
*leaf
;
379 leaf
= path
->nodes
[0];
380 dir_item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_dir_item
);
381 if (verify_dir_item(root
, leaf
, dir_item
))
384 total_len
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
385 while (cur
< total_len
) {
386 this_len
= sizeof(*dir_item
) +
387 btrfs_dir_name_len(leaf
, dir_item
) +
388 btrfs_dir_data_len(leaf
, dir_item
);
389 name_ptr
= (unsigned long)(dir_item
+ 1);
391 if (btrfs_dir_name_len(leaf
, dir_item
) == name_len
&&
392 memcmp_extent_buffer(leaf
, name
, name_ptr
, name_len
) == 0)
396 dir_item
= (struct btrfs_dir_item
*)((char *)dir_item
+
403 * given a pointer into a directory item, delete it. This
404 * handles items that have more than one entry in them.
406 int btrfs_delete_one_dir_name(struct btrfs_trans_handle
*trans
,
407 struct btrfs_root
*root
,
408 struct btrfs_path
*path
,
409 struct btrfs_dir_item
*di
)
412 struct extent_buffer
*leaf
;
417 leaf
= path
->nodes
[0];
418 sub_item_len
= sizeof(*di
) + btrfs_dir_name_len(leaf
, di
) +
419 btrfs_dir_data_len(leaf
, di
);
420 item_len
= btrfs_item_size_nr(leaf
, path
->slots
[0]);
421 if (sub_item_len
== item_len
) {
422 ret
= btrfs_del_item(trans
, root
, path
);
425 unsigned long ptr
= (unsigned long)di
;
428 start
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
429 memmove_extent_buffer(leaf
, ptr
, ptr
+ sub_item_len
,
430 item_len
- (ptr
+ sub_item_len
- start
));
431 ret
= btrfs_truncate_item(trans
, root
, path
,
432 item_len
- sub_item_len
, 1);
437 int verify_dir_item(struct btrfs_root
*root
,
438 struct extent_buffer
*leaf
,
439 struct btrfs_dir_item
*dir_item
)
441 u16 namelen
= BTRFS_NAME_LEN
;
442 u8 type
= btrfs_dir_type(leaf
, dir_item
);
444 if (type
>= BTRFS_FT_MAX
) {
445 printk(KERN_CRIT
"btrfs: invalid dir item type: %d\n",
450 if (type
== BTRFS_FT_XATTR
)
451 namelen
= XATTR_NAME_MAX
;
453 if (btrfs_dir_name_len(leaf
, dir_item
) > namelen
) {
454 printk(KERN_CRIT
"btrfs: invalid dir item name len: %u\n",
455 (unsigned)btrfs_dir_data_len(leaf
, dir_item
));
459 /* BTRFS_MAX_XATTR_SIZE is the same for all dir items */
460 if (btrfs_dir_data_len(leaf
, dir_item
) > BTRFS_MAX_XATTR_SIZE(root
)) {
461 printk(KERN_CRIT
"btrfs: invalid dir item data len: %u\n",
462 (unsigned)btrfs_dir_data_len(leaf
, dir_item
));