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6#include "ctree.h"
7#include "disk-io.h"
8#include "transaction.h"
9
10
11
12
13
14
15
16
17
18static struct btrfs_dir_item *insert_with_overflow(struct btrfs_trans_handle
19 *trans,
20 struct btrfs_root *root,
21 struct btrfs_path *path,
22 struct btrfs_key *cpu_key,
23 u32 data_size,
24 const char *name,
25 int name_len)
26{
27 struct btrfs_fs_info *fs_info = root->fs_info;
28 int ret;
29 char *ptr;
30 struct btrfs_item *item;
31 struct extent_buffer *leaf;
32
33 ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size);
34 if (ret == -EEXIST) {
35 struct btrfs_dir_item *di;
36 di = btrfs_match_dir_item_name(fs_info, path, name, name_len);
37 if (di)
38 return ERR_PTR(-EEXIST);
39 btrfs_extend_item(path, data_size);
40 } else if (ret < 0)
41 return ERR_PTR(ret);
42 WARN_ON(ret > 0);
43 leaf = path->nodes[0];
44 item = btrfs_item_nr(path->slots[0]);
45 ptr = btrfs_item_ptr(leaf, path->slots[0], char);
46 BUG_ON(data_size > btrfs_item_size(leaf, item));
47 ptr += btrfs_item_size(leaf, item) - data_size;
48 return (struct btrfs_dir_item *)ptr;
49}
50
51
52
53
54
55int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans,
56 struct btrfs_root *root,
57 struct btrfs_path *path, u64 objectid,
58 const char *name, u16 name_len,
59 const void *data, u16 data_len)
60{
61 int ret = 0;
62 struct btrfs_dir_item *dir_item;
63 unsigned long name_ptr, data_ptr;
64 struct btrfs_key key, location;
65 struct btrfs_disk_key disk_key;
66 struct extent_buffer *leaf;
67 u32 data_size;
68
69 if (name_len + data_len > BTRFS_MAX_XATTR_SIZE(root->fs_info))
70 return -ENOSPC;
71
72 key.objectid = objectid;
73 key.type = BTRFS_XATTR_ITEM_KEY;
74 key.offset = btrfs_name_hash(name, name_len);
75
76 data_size = sizeof(*dir_item) + name_len + data_len;
77 dir_item = insert_with_overflow(trans, root, path, &key, data_size,
78 name, name_len);
79 if (IS_ERR(dir_item))
80 return PTR_ERR(dir_item);
81 memset(&location, 0, sizeof(location));
82
83 leaf = path->nodes[0];
84 btrfs_cpu_key_to_disk(&disk_key, &location);
85 btrfs_set_dir_item_key(leaf, dir_item, &disk_key);
86 btrfs_set_dir_type(leaf, dir_item, BTRFS_FT_XATTR);
87 btrfs_set_dir_name_len(leaf, dir_item, name_len);
88 btrfs_set_dir_transid(leaf, dir_item, trans->transid);
89 btrfs_set_dir_data_len(leaf, dir_item, data_len);
90 name_ptr = (unsigned long)(dir_item + 1);
91 data_ptr = (unsigned long)((char *)name_ptr + name_len);
92
93 write_extent_buffer(leaf, name, name_ptr, name_len);
94 write_extent_buffer(leaf, data, data_ptr, data_len);
95 btrfs_mark_buffer_dirty(path->nodes[0]);
96
97 return ret;
98}
99
100
101
102
103
104
105
106
107
108int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, const char *name,
109 int name_len, struct btrfs_inode *dir,
110 struct btrfs_key *location, u8 type, u64 index)
111{
112 int ret = 0;
113 int ret2 = 0;
114 struct btrfs_root *root = dir->root;
115 struct btrfs_path *path;
116 struct btrfs_dir_item *dir_item;
117 struct extent_buffer *leaf;
118 unsigned long name_ptr;
119 struct btrfs_key key;
120 struct btrfs_disk_key disk_key;
121 u32 data_size;
122
123 key.objectid = btrfs_ino(dir);
124 key.type = BTRFS_DIR_ITEM_KEY;
125 key.offset = btrfs_name_hash(name, name_len);
126
127 path = btrfs_alloc_path();
128 if (!path)
129 return -ENOMEM;
130
131 btrfs_cpu_key_to_disk(&disk_key, location);
132
133 data_size = sizeof(*dir_item) + name_len;
134 dir_item = insert_with_overflow(trans, root, path, &key, data_size,
135 name, name_len);
136 if (IS_ERR(dir_item)) {
137 ret = PTR_ERR(dir_item);
138 if (ret == -EEXIST)
139 goto second_insert;
140 goto out_free;
141 }
142
143 leaf = path->nodes[0];
144 btrfs_set_dir_item_key(leaf, dir_item, &disk_key);
145 btrfs_set_dir_type(leaf, dir_item, type);
146 btrfs_set_dir_data_len(leaf, dir_item, 0);
147 btrfs_set_dir_name_len(leaf, dir_item, name_len);
148 btrfs_set_dir_transid(leaf, dir_item, trans->transid);
149 name_ptr = (unsigned long)(dir_item + 1);
150
151 write_extent_buffer(leaf, name, name_ptr, name_len);
152 btrfs_mark_buffer_dirty(leaf);
153
154second_insert:
155
156 if (root == root->fs_info->tree_root) {
157 ret = 0;
158 goto out_free;
159 }
160 btrfs_release_path(path);
161
162 ret2 = btrfs_insert_delayed_dir_index(trans, name, name_len, dir,
163 &disk_key, type, index);
164out_free:
165 btrfs_free_path(path);
166 if (ret)
167 return ret;
168 if (ret2)
169 return ret2;
170 return 0;
171}
172
173
174
175
176
177
178struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
179 struct btrfs_root *root,
180 struct btrfs_path *path, u64 dir,
181 const char *name, int name_len,
182 int mod)
183{
184 int ret;
185 struct btrfs_key key;
186 int ins_len = mod < 0 ? -1 : 0;
187 int cow = mod != 0;
188
189 key.objectid = dir;
190 key.type = BTRFS_DIR_ITEM_KEY;
191
192 key.offset = btrfs_name_hash(name, name_len);
193
194 ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
195 if (ret < 0)
196 return ERR_PTR(ret);
197 if (ret > 0)
198 return NULL;
199
200 return btrfs_match_dir_item_name(root->fs_info, path, name, name_len);
201}
202
203int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
204 const char *name, int name_len)
205{
206 int ret;
207 struct btrfs_key key;
208 struct btrfs_dir_item *di;
209 int data_size;
210 struct extent_buffer *leaf;
211 int slot;
212 struct btrfs_path *path;
213
214
215 path = btrfs_alloc_path();
216 if (!path)
217 return -ENOMEM;
218
219 key.objectid = dir;
220 key.type = BTRFS_DIR_ITEM_KEY;
221 key.offset = btrfs_name_hash(name, name_len);
222
223 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
224
225
226 if (ret < 0)
227 goto out;
228
229
230 if (ret > 0) {
231 ret = 0;
232 goto out;
233 }
234
235
236 di = btrfs_match_dir_item_name(root->fs_info, path, name, name_len);
237 if (di) {
238
239 ret = -EEXIST;
240 goto out;
241 }
242
243
244
245
246
247 data_size = sizeof(*di) + name_len;
248 leaf = path->nodes[0];
249 slot = path->slots[0];
250 if (data_size + btrfs_item_size_nr(leaf, slot) +
251 sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
252 ret = -EOVERFLOW;
253 } else {
254
255 ret = 0;
256 }
257out:
258 btrfs_free_path(path);
259 return ret;
260}
261
262
263
264
265
266
267
268
269
270struct btrfs_dir_item *
271btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
272 struct btrfs_root *root,
273 struct btrfs_path *path, u64 dir,
274 u64 objectid, const char *name, int name_len,
275 int mod)
276{
277 int ret;
278 struct btrfs_key key;
279 int ins_len = mod < 0 ? -1 : 0;
280 int cow = mod != 0;
281
282 key.objectid = dir;
283 key.type = BTRFS_DIR_INDEX_KEY;
284 key.offset = objectid;
285
286 ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
287 if (ret < 0)
288 return ERR_PTR(ret);
289 if (ret > 0)
290 return ERR_PTR(-ENOENT);
291 return btrfs_match_dir_item_name(root->fs_info, path, name, name_len);
292}
293
294struct btrfs_dir_item *
295btrfs_search_dir_index_item(struct btrfs_root *root,
296 struct btrfs_path *path, u64 dirid,
297 const char *name, int name_len)
298{
299 struct extent_buffer *leaf;
300 struct btrfs_dir_item *di;
301 struct btrfs_key key;
302 u32 nritems;
303 int ret;
304
305 key.objectid = dirid;
306 key.type = BTRFS_DIR_INDEX_KEY;
307 key.offset = 0;
308
309 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
310 if (ret < 0)
311 return ERR_PTR(ret);
312
313 leaf = path->nodes[0];
314 nritems = btrfs_header_nritems(leaf);
315
316 while (1) {
317 if (path->slots[0] >= nritems) {
318 ret = btrfs_next_leaf(root, path);
319 if (ret < 0)
320 return ERR_PTR(ret);
321 if (ret > 0)
322 break;
323 leaf = path->nodes[0];
324 nritems = btrfs_header_nritems(leaf);
325 continue;
326 }
327
328 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
329 if (key.objectid != dirid || key.type != BTRFS_DIR_INDEX_KEY)
330 break;
331
332 di = btrfs_match_dir_item_name(root->fs_info, path,
333 name, name_len);
334 if (di)
335 return di;
336
337 path->slots[0]++;
338 }
339 return NULL;
340}
341
342struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans,
343 struct btrfs_root *root,
344 struct btrfs_path *path, u64 dir,
345 const char *name, u16 name_len,
346 int mod)
347{
348 int ret;
349 struct btrfs_key key;
350 int ins_len = mod < 0 ? -1 : 0;
351 int cow = mod != 0;
352
353 key.objectid = dir;
354 key.type = BTRFS_XATTR_ITEM_KEY;
355 key.offset = btrfs_name_hash(name, name_len);
356 ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
357 if (ret < 0)
358 return ERR_PTR(ret);
359 if (ret > 0)
360 return NULL;
361
362 return btrfs_match_dir_item_name(root->fs_info, path, name, name_len);
363}
364
365
366
367
368
369
370struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_fs_info *fs_info,
371 struct btrfs_path *path,
372 const char *name, int name_len)
373{
374 struct btrfs_dir_item *dir_item;
375 unsigned long name_ptr;
376 u32 total_len;
377 u32 cur = 0;
378 u32 this_len;
379 struct extent_buffer *leaf;
380
381 leaf = path->nodes[0];
382 dir_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item);
383
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);
390
391 if (btrfs_dir_name_len(leaf, dir_item) == name_len &&
392 memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0)
393 return dir_item;
394
395 cur += this_len;
396 dir_item = (struct btrfs_dir_item *)((char *)dir_item +
397 this_len);
398 }
399 return NULL;
400}
401
402
403
404
405
406int 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)
410{
411
412 struct extent_buffer *leaf;
413 u32 sub_item_len;
414 u32 item_len;
415 int ret = 0;
416
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);
423 } else {
424
425 unsigned long ptr = (unsigned long)di;
426 unsigned long start;
427
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 btrfs_truncate_item(path, item_len - sub_item_len, 1);
432 }
433 return ret;
434}
435