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.
21 #include "transaction.h"
24 static int find_name_in_backref(struct btrfs_path *path, const char * name,
25 int name_len, struct btrfs_inode_ref **ref_ret)
27 struct extent_buffer *leaf;
28 struct btrfs_inode_ref *ref;
30 unsigned long name_ptr;
35 leaf = path->nodes[0];
36 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
37 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
38 while (cur_offset < item_size) {
39 ref = (struct btrfs_inode_ref *)(ptr + cur_offset);
40 len = btrfs_inode_ref_name_len(leaf, ref);
41 name_ptr = (unsigned long)(ref + 1);
42 cur_offset += len + sizeof(*ref);
45 if (memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0) {
53 int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
54 struct btrfs_root *root,
55 const char *name, int name_len,
56 u64 inode_objectid, u64 ref_objectid, u64 index)
58 struct btrfs_path *path;
60 struct btrfs_inode_ref *ref;
63 int ins_len = name_len + sizeof(*ref);
65 key.objectid = inode_objectid;
66 key.offset = ref_objectid;
67 key.type = BTRFS_INODE_REF_KEY;
69 path = btrfs_alloc_path();
73 ret = btrfs_insert_empty_item(trans, root, path, &key,
78 if (find_name_in_backref(path, name, name_len, &ref))
81 old_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
82 ret = btrfs_extend_item(trans, root, path, ins_len);
84 ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
85 struct btrfs_inode_ref);
86 ref = (struct btrfs_inode_ref *)((unsigned long)ref + old_size);
87 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
88 btrfs_set_inode_ref_index(path->nodes[0], ref, index);
89 ptr = (unsigned long)(ref + 1);
92 if (ret == -EOVERFLOW)
96 ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
97 struct btrfs_inode_ref);
98 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
99 btrfs_set_inode_ref_index(path->nodes[0], ref, index);
100 ptr = (unsigned long)(ref + 1);
102 write_extent_buffer(path->nodes[0], name, ptr, name_len);
103 btrfs_mark_buffer_dirty(path->nodes[0]);
106 btrfs_free_path(path);
108 if (ret == -EMLINK) {
109 if (btrfs_fs_incompat(root->fs_info,
110 BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF))
111 ret = btrfs_insert_inode_extref(trans, root, name,
114 ref_objectid, index);
119 int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root
120 *root, struct btrfs_path *path,
121 struct btrfs_key *location, int mod)
123 int ins_len = mod < 0 ? -1 : 0;
127 struct extent_buffer *leaf;
128 struct btrfs_key found_key;
130 ret = btrfs_search_slot(trans, root, location, path, ins_len, cow);
131 if (ret > 0 && location->type == BTRFS_ROOT_ITEM_KEY &&
132 location->offset == (u64)-1 && path->slots[0] != 0) {
133 slot = path->slots[0] - 1;
134 leaf = path->nodes[0];
135 btrfs_item_key_to_cpu(leaf, &found_key, slot);
136 if (found_key.objectid == location->objectid &&
137 found_key.type == location->type) {
145 int btrfs_insert_inode(struct btrfs_trans_handle *trans, struct btrfs_root
146 *root, u64 objectid, struct btrfs_inode_item
150 struct btrfs_key key;
152 key.objectid = objectid;
153 key.type = BTRFS_INODE_ITEM_KEY;
156 ret = btrfs_insert_item(trans, root, &key, inode_item,
157 sizeof(*inode_item));
161 struct btrfs_inode_ref *btrfs_lookup_inode_ref(struct btrfs_trans_handle *trans,
162 struct btrfs_root *root, struct btrfs_path *path,
163 const char *name, int namelen, u64 ino, u64 parent_ino,
164 u64 index, int ins_len)
166 struct btrfs_key key;
167 struct btrfs_inode_ref *ret_inode_ref = NULL;
171 key.type = BTRFS_INODE_REF_KEY;
172 key.offset = parent_ino;
174 ret = btrfs_search_slot(trans, root, &key, path, ins_len,
179 find_name_in_backref(path, name, namelen, &ret_inode_ref);
184 return ret_inode_ref;
187 static int btrfs_find_name_in_ext_backref(struct btrfs_path *path,
188 u64 parent_ino, const char *name, int namelen,
189 struct btrfs_inode_extref **extref_ret)
191 struct extent_buffer *node;
192 struct btrfs_inode_extref *extref;
194 unsigned long name_ptr;
200 node = path->nodes[0];
201 slot = path->slots[0];
202 item_size = btrfs_item_size_nr(node, slot);
203 ptr = btrfs_item_ptr_offset(node, slot);
206 * Search all extended backrefs in this item. We're only looking
207 * through any collisions so most of the time this is just going to
208 * compare against one buffer. If all is well, we'll return success and
209 * the inode ref object.
211 while (cur_offset < item_size) {
212 extref = (struct btrfs_inode_extref *) (ptr + cur_offset);
213 name_ptr = (unsigned long)(&extref->name);
214 ref_name_len = btrfs_inode_extref_name_len(node, extref);
216 if (ref_name_len == namelen &&
217 btrfs_inode_extref_parent(node, extref) == parent_ino &&
218 (memcmp_extent_buffer(node, name, name_ptr, namelen) == 0))
221 *extref_ret = extref;
225 cur_offset += ref_name_len + sizeof(*extref);
231 struct btrfs_inode_extref *btrfs_lookup_inode_extref(struct btrfs_trans_handle
232 *trans, struct btrfs_path *path, struct btrfs_root *root,
233 u64 ino, u64 parent_ino, u64 index, const char *name,
234 int namelen, int ins_len)
236 struct btrfs_key key;
237 struct btrfs_inode_extref *extref;
241 key.type = BTRFS_INODE_EXTREF_KEY;
242 key.offset = btrfs_extref_hash(parent_ino, name, namelen);
244 ret = btrfs_search_slot(trans, root, &key, path, ins_len,
250 if (!btrfs_find_name_in_ext_backref(path, parent_ino, name,
257 int btrfs_del_inode_extref(struct btrfs_trans_handle *trans,
258 struct btrfs_root *root,
259 const char *name, int name_len,
260 u64 inode_objectid, u64 ref_objectid,
263 struct btrfs_path *path;
264 struct btrfs_key key;
265 struct btrfs_inode_extref *extref;
266 struct extent_buffer *leaf;
268 int del_len = name_len + sizeof(*extref);
270 unsigned long item_start;
273 key.objectid = inode_objectid;
274 key.type = BTRFS_INODE_EXTREF_KEY;
275 key.offset = btrfs_extref_hash(ref_objectid, name, name_len);
277 path = btrfs_alloc_path();
281 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
288 * Sanity check - did we find the right item for this name? This
289 * should always succeed so error here will make the FS readonly.
291 if (!btrfs_find_name_in_ext_backref(path, ref_objectid,
292 name, name_len, &extref)) {
297 leaf = path->nodes[0];
298 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
300 *index = btrfs_inode_extref_index(leaf, extref);
302 if (del_len == item_size) {
304 * Common case only one ref in the item, remove the whole item.
306 ret = btrfs_del_item(trans, root, path);
310 ptr = (unsigned long)extref;
311 item_start = btrfs_item_ptr_offset(leaf, path->slots[0]);
313 memmove_extent_buffer(leaf, ptr, ptr + del_len,
314 item_size - (ptr + del_len - item_start));
316 btrfs_truncate_item(trans, root, path, item_size - del_len, 1);
319 btrfs_free_path(path);
325 * btrfs_insert_inode_extref() - Inserts an extended inode ref into a tree.
327 * The caller must have checked against BTRFS_LINK_MAX already.
329 int btrfs_insert_inode_extref(struct btrfs_trans_handle *trans,
330 struct btrfs_root *root,
331 const char *name, int name_len,
332 u64 inode_objectid, u64 ref_objectid, u64 index)
334 struct btrfs_inode_extref *extref;
336 int ins_len = name_len + sizeof(*extref);
338 struct btrfs_path *path;
339 struct btrfs_key key;
340 struct extent_buffer *leaf;
341 struct btrfs_item *item;
343 key.objectid = inode_objectid;
344 key.type = BTRFS_INODE_EXTREF_KEY;
345 key.offset = btrfs_extref_hash(ref_objectid, name, name_len);
347 path = btrfs_alloc_path();
351 ret = btrfs_insert_empty_item(trans, root, path, &key,
353 if (ret == -EEXIST) {
354 if (btrfs_find_name_in_ext_backref(path, ref_objectid,
355 name, name_len, NULL))
358 btrfs_extend_item(trans, root, path, ins_len);
365 leaf = path->nodes[0];
366 item = btrfs_item_nr(path->slots[0]);
367 ptr = (unsigned long)btrfs_item_ptr(leaf, path->slots[0], char);
368 ptr += btrfs_item_size(leaf, item) - ins_len;
369 extref = (struct btrfs_inode_extref *)ptr;
371 btrfs_set_inode_extref_name_len(path->nodes[0], extref, name_len);
372 btrfs_set_inode_extref_index(path->nodes[0], extref, index);
373 btrfs_set_inode_extref_parent(path->nodes[0], extref, ref_objectid);
375 ptr = (unsigned long)&extref->name;
376 write_extent_buffer(path->nodes[0], name, ptr, name_len);
377 btrfs_mark_buffer_dirty(path->nodes[0]);
380 btrfs_free_path(path);
385 int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
386 struct btrfs_root *root, const char *name, int name_len,
387 u64 ino, u64 parent_ino, u64 *index)
389 struct btrfs_path *path;
390 struct btrfs_key key;
391 struct btrfs_inode_ref *ref;
392 struct extent_buffer *leaf;
394 unsigned long item_start;
398 int search_ext_refs = 0;
399 int del_len = name_len + sizeof(*ref);
402 key.offset = parent_ino;
403 key.type = BTRFS_INODE_REF_KEY;
405 path = btrfs_alloc_path();
409 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
414 } else if (ret < 0) {
417 if (!find_name_in_backref(path, name, name_len, &ref)) {
422 leaf = path->nodes[0];
423 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
426 *index = btrfs_inode_ref_index(leaf, ref);
428 if (del_len == item_size) {
429 ret = btrfs_del_item(trans, root, path);
432 ptr = (unsigned long)ref;
433 sub_item_len = name_len + sizeof(*ref);
434 item_start = btrfs_item_ptr_offset(leaf, path->slots[0]);
435 memmove_extent_buffer(leaf, ptr, ptr + sub_item_len,
436 item_size - (ptr + sub_item_len - item_start));
437 btrfs_truncate_item(trans, root, path, item_size - sub_item_len, 1);
438 btrfs_mark_buffer_dirty(path->nodes[0]);
440 btrfs_free_path(path);
442 if (search_ext_refs &&
443 btrfs_fs_incompat(root->fs_info,
444 BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF)) {
446 * No refs were found, or we could not find the name in our ref
447 * array. Find and remove the extended inode ref then.
449 return btrfs_del_inode_extref(trans, root, name, name_len,
450 ino, parent_ino, index);