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6#include "ctree.h"
7#include "disk-io.h"
8#include "transaction.h"
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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}
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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}
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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
173static struct btrfs_dir_item *btrfs_lookup_match_dir(
174 struct btrfs_trans_handle *trans,
175 struct btrfs_root *root, struct btrfs_path *path,
176 struct btrfs_key *key, const char *name,
177 int name_len, int mod)
178{
179 const int ins_len = (mod < 0 ? -1 : 0);
180 const int cow = (mod != 0);
181 int ret;
182
183 ret = btrfs_search_slot(trans, root, key, path, ins_len, cow);
184 if (ret < 0)
185 return ERR_PTR(ret);
186 if (ret > 0)
187 return ERR_PTR(-ENOENT);
188
189 return btrfs_match_dir_item_name(root->fs_info, path, name, name_len);
190}
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208struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
209 struct btrfs_root *root,
210 struct btrfs_path *path, u64 dir,
211 const char *name, int name_len,
212 int mod)
213{
214 struct btrfs_key key;
215 struct btrfs_dir_item *di;
216
217 key.objectid = dir;
218 key.type = BTRFS_DIR_ITEM_KEY;
219 key.offset = btrfs_name_hash(name, name_len);
220
221 di = btrfs_lookup_match_dir(trans, root, path, &key, name, name_len, mod);
222 if (IS_ERR(di) && PTR_ERR(di) == -ENOENT)
223 return NULL;
224
225 return di;
226}
227
228int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
229 const char *name, int name_len)
230{
231 int ret;
232 struct btrfs_key key;
233 struct btrfs_dir_item *di;
234 int data_size;
235 struct extent_buffer *leaf;
236 int slot;
237 struct btrfs_path *path;
238
239 path = btrfs_alloc_path();
240 if (!path)
241 return -ENOMEM;
242
243 key.objectid = dir;
244 key.type = BTRFS_DIR_ITEM_KEY;
245 key.offset = btrfs_name_hash(name, name_len);
246
247 di = btrfs_lookup_match_dir(NULL, root, path, &key, name, name_len, 0);
248 if (IS_ERR(di)) {
249 ret = PTR_ERR(di);
250
251 if (ret == -ENOENT) {
252 ret = 0;
253 goto out;
254 }
255
256 if (ret < 0)
257 goto out;
258 }
259
260
261 if (di) {
262
263 ret = -EEXIST;
264 goto out;
265 }
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270
271 data_size = sizeof(*di) + name_len;
272 leaf = path->nodes[0];
273 slot = path->slots[0];
274 if (data_size + btrfs_item_size_nr(leaf, slot) +
275 sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
276 ret = -EOVERFLOW;
277 } else {
278
279 ret = 0;
280 }
281out:
282 btrfs_free_path(path);
283 return ret;
284}
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303
304struct btrfs_dir_item *
305btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
306 struct btrfs_root *root,
307 struct btrfs_path *path, u64 dir,
308 u64 index, const char *name, int name_len,
309 int mod)
310{
311 struct btrfs_dir_item *di;
312 struct btrfs_key key;
313
314 key.objectid = dir;
315 key.type = BTRFS_DIR_INDEX_KEY;
316 key.offset = index;
317
318 di = btrfs_lookup_match_dir(trans, root, path, &key, name, name_len, mod);
319 if (di == ERR_PTR(-ENOENT))
320 return NULL;
321
322 return di;
323}
324
325struct btrfs_dir_item *
326btrfs_search_dir_index_item(struct btrfs_root *root,
327 struct btrfs_path *path, u64 dirid,
328 const char *name, int name_len)
329{
330 struct extent_buffer *leaf;
331 struct btrfs_dir_item *di;
332 struct btrfs_key key;
333 u32 nritems;
334 int ret;
335
336 key.objectid = dirid;
337 key.type = BTRFS_DIR_INDEX_KEY;
338 key.offset = 0;
339
340 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
341 if (ret < 0)
342 return ERR_PTR(ret);
343
344 leaf = path->nodes[0];
345 nritems = btrfs_header_nritems(leaf);
346
347 while (1) {
348 if (path->slots[0] >= nritems) {
349 ret = btrfs_next_leaf(root, path);
350 if (ret < 0)
351 return ERR_PTR(ret);
352 if (ret > 0)
353 break;
354 leaf = path->nodes[0];
355 nritems = btrfs_header_nritems(leaf);
356 continue;
357 }
358
359 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
360 if (key.objectid != dirid || key.type != BTRFS_DIR_INDEX_KEY)
361 break;
362
363 di = btrfs_match_dir_item_name(root->fs_info, path,
364 name, name_len);
365 if (di)
366 return di;
367
368 path->slots[0]++;
369 }
370 return NULL;
371}
372
373struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans,
374 struct btrfs_root *root,
375 struct btrfs_path *path, u64 dir,
376 const char *name, u16 name_len,
377 int mod)
378{
379 struct btrfs_key key;
380 struct btrfs_dir_item *di;
381
382 key.objectid = dir;
383 key.type = BTRFS_XATTR_ITEM_KEY;
384 key.offset = btrfs_name_hash(name, name_len);
385
386 di = btrfs_lookup_match_dir(trans, root, path, &key, name, name_len, mod);
387 if (IS_ERR(di) && PTR_ERR(di) == -ENOENT)
388 return NULL;
389
390 return di;
391}
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397
398struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_fs_info *fs_info,
399 struct btrfs_path *path,
400 const char *name, int name_len)
401{
402 struct btrfs_dir_item *dir_item;
403 unsigned long name_ptr;
404 u32 total_len;
405 u32 cur = 0;
406 u32 this_len;
407 struct extent_buffer *leaf;
408
409 leaf = path->nodes[0];
410 dir_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item);
411
412 total_len = btrfs_item_size_nr(leaf, path->slots[0]);
413 while (cur < total_len) {
414 this_len = sizeof(*dir_item) +
415 btrfs_dir_name_len(leaf, dir_item) +
416 btrfs_dir_data_len(leaf, dir_item);
417 name_ptr = (unsigned long)(dir_item + 1);
418
419 if (btrfs_dir_name_len(leaf, dir_item) == name_len &&
420 memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0)
421 return dir_item;
422
423 cur += this_len;
424 dir_item = (struct btrfs_dir_item *)((char *)dir_item +
425 this_len);
426 }
427 return NULL;
428}
429
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433
434int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans,
435 struct btrfs_root *root,
436 struct btrfs_path *path,
437 struct btrfs_dir_item *di)
438{
439
440 struct extent_buffer *leaf;
441 u32 sub_item_len;
442 u32 item_len;
443 int ret = 0;
444
445 leaf = path->nodes[0];
446 sub_item_len = sizeof(*di) + btrfs_dir_name_len(leaf, di) +
447 btrfs_dir_data_len(leaf, di);
448 item_len = btrfs_item_size_nr(leaf, path->slots[0]);
449 if (sub_item_len == item_len) {
450 ret = btrfs_del_item(trans, root, path);
451 } else {
452
453 unsigned long ptr = (unsigned long)di;
454 unsigned long start;
455
456 start = btrfs_item_ptr_offset(leaf, path->slots[0]);
457 memmove_extent_buffer(leaf, ptr, ptr + sub_item_len,
458 item_len - (ptr + sub_item_len - start));
459 btrfs_truncate_item(path, item_len - sub_item_len, 1);
460 }
461 return ret;
462}
463