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18#include <linux/uuid.h>
19#include <asm/unaligned.h>
20#include "ctree.h"
21#include "transaction.h"
22#include "disk-io.h"
23#include "print-tree.h"
24
25
26static void btrfs_uuid_to_key(u8 *uuid, u8 type, struct btrfs_key *key)
27{
28 key->type = type;
29 key->objectid = get_unaligned_le64(uuid);
30 key->offset = get_unaligned_le64(uuid + sizeof(u64));
31}
32
33
34static int btrfs_uuid_tree_lookup(struct btrfs_root *uuid_root, u8 *uuid,
35 u8 type, u64 subid)
36{
37 int ret;
38 struct btrfs_path *path = NULL;
39 struct extent_buffer *eb;
40 int slot;
41 u32 item_size;
42 unsigned long offset;
43 struct btrfs_key key;
44
45 if (WARN_ON_ONCE(!uuid_root)) {
46 ret = -ENOENT;
47 goto out;
48 }
49
50 path = btrfs_alloc_path();
51 if (!path) {
52 ret = -ENOMEM;
53 goto out;
54 }
55
56 btrfs_uuid_to_key(uuid, type, &key);
57 ret = btrfs_search_slot(NULL, uuid_root, &key, path, 0, 0);
58 if (ret < 0) {
59 goto out;
60 } else if (ret > 0) {
61 ret = -ENOENT;
62 goto out;
63 }
64
65 eb = path->nodes[0];
66 slot = path->slots[0];
67 item_size = btrfs_item_size_nr(eb, slot);
68 offset = btrfs_item_ptr_offset(eb, slot);
69 ret = -ENOENT;
70
71 if (!IS_ALIGNED(item_size, sizeof(u64))) {
72 btrfs_warn(uuid_root->fs_info,
73 "uuid item with illegal size %lu!",
74 (unsigned long)item_size);
75 goto out;
76 }
77 while (item_size) {
78 __le64 data;
79
80 read_extent_buffer(eb, &data, offset, sizeof(data));
81 if (le64_to_cpu(data) == subid) {
82 ret = 0;
83 break;
84 }
85 offset += sizeof(data);
86 item_size -= sizeof(data);
87 }
88
89out:
90 btrfs_free_path(path);
91 return ret;
92}
93
94int btrfs_uuid_tree_add(struct btrfs_trans_handle *trans,
95 struct btrfs_fs_info *fs_info, u8 *uuid, u8 type,
96 u64 subid_cpu)
97{
98 struct btrfs_root *uuid_root = fs_info->uuid_root;
99 int ret;
100 struct btrfs_path *path = NULL;
101 struct btrfs_key key;
102 struct extent_buffer *eb;
103 int slot;
104 unsigned long offset;
105 __le64 subid_le;
106
107 ret = btrfs_uuid_tree_lookup(uuid_root, uuid, type, subid_cpu);
108 if (ret != -ENOENT)
109 return ret;
110
111 if (WARN_ON_ONCE(!uuid_root)) {
112 ret = -EINVAL;
113 goto out;
114 }
115
116 btrfs_uuid_to_key(uuid, type, &key);
117
118 path = btrfs_alloc_path();
119 if (!path) {
120 ret = -ENOMEM;
121 goto out;
122 }
123
124 ret = btrfs_insert_empty_item(trans, uuid_root, path, &key,
125 sizeof(subid_le));
126 if (ret >= 0) {
127
128 eb = path->nodes[0];
129 slot = path->slots[0];
130 offset = btrfs_item_ptr_offset(eb, slot);
131 } else if (ret == -EEXIST) {
132
133
134
135
136 btrfs_extend_item(fs_info, path, sizeof(subid_le));
137 eb = path->nodes[0];
138 slot = path->slots[0];
139 offset = btrfs_item_ptr_offset(eb, slot);
140 offset += btrfs_item_size_nr(eb, slot) - sizeof(subid_le);
141 } else if (ret < 0) {
142 btrfs_warn(fs_info,
143 "insert uuid item failed %d (0x%016llx, 0x%016llx) type %u!",
144 ret, (unsigned long long)key.objectid,
145 (unsigned long long)key.offset, type);
146 goto out;
147 }
148
149 ret = 0;
150 subid_le = cpu_to_le64(subid_cpu);
151 write_extent_buffer(eb, &subid_le, offset, sizeof(subid_le));
152 btrfs_mark_buffer_dirty(eb);
153
154out:
155 btrfs_free_path(path);
156 return ret;
157}
158
159int btrfs_uuid_tree_rem(struct btrfs_trans_handle *trans,
160 struct btrfs_fs_info *fs_info, u8 *uuid, u8 type,
161 u64 subid)
162{
163 struct btrfs_root *uuid_root = fs_info->uuid_root;
164 int ret;
165 struct btrfs_path *path = NULL;
166 struct btrfs_key key;
167 struct extent_buffer *eb;
168 int slot;
169 unsigned long offset;
170 u32 item_size;
171 unsigned long move_dst;
172 unsigned long move_src;
173 unsigned long move_len;
174
175 if (WARN_ON_ONCE(!uuid_root)) {
176 ret = -EINVAL;
177 goto out;
178 }
179
180 btrfs_uuid_to_key(uuid, type, &key);
181
182 path = btrfs_alloc_path();
183 if (!path) {
184 ret = -ENOMEM;
185 goto out;
186 }
187
188 ret = btrfs_search_slot(trans, uuid_root, &key, path, -1, 1);
189 if (ret < 0) {
190 btrfs_warn(fs_info, "error %d while searching for uuid item!",
191 ret);
192 goto out;
193 }
194 if (ret > 0) {
195 ret = -ENOENT;
196 goto out;
197 }
198
199 eb = path->nodes[0];
200 slot = path->slots[0];
201 offset = btrfs_item_ptr_offset(eb, slot);
202 item_size = btrfs_item_size_nr(eb, slot);
203 if (!IS_ALIGNED(item_size, sizeof(u64))) {
204 btrfs_warn(fs_info, "uuid item with illegal size %lu!",
205 (unsigned long)item_size);
206 ret = -ENOENT;
207 goto out;
208 }
209 while (item_size) {
210 __le64 read_subid;
211
212 read_extent_buffer(eb, &read_subid, offset, sizeof(read_subid));
213 if (le64_to_cpu(read_subid) == subid)
214 break;
215 offset += sizeof(read_subid);
216 item_size -= sizeof(read_subid);
217 }
218
219 if (!item_size) {
220 ret = -ENOENT;
221 goto out;
222 }
223
224 item_size = btrfs_item_size_nr(eb, slot);
225 if (item_size == sizeof(subid)) {
226 ret = btrfs_del_item(trans, uuid_root, path);
227 goto out;
228 }
229
230 move_dst = offset;
231 move_src = offset + sizeof(subid);
232 move_len = item_size - (move_src - btrfs_item_ptr_offset(eb, slot));
233 memmove_extent_buffer(eb, move_dst, move_src, move_len);
234 btrfs_truncate_item(fs_info, path, item_size - sizeof(subid), 1);
235
236out:
237 btrfs_free_path(path);
238 return ret;
239}
240
241static int btrfs_uuid_iter_rem(struct btrfs_root *uuid_root, u8 *uuid, u8 type,
242 u64 subid)
243{
244 struct btrfs_trans_handle *trans;
245 int ret;
246
247
248 trans = btrfs_start_transaction(uuid_root, 1);
249 if (IS_ERR(trans)) {
250 ret = PTR_ERR(trans);
251 goto out;
252 }
253
254 ret = btrfs_uuid_tree_rem(trans, uuid_root->fs_info, uuid, type, subid);
255 btrfs_end_transaction(trans);
256
257out:
258 return ret;
259}
260
261int btrfs_uuid_tree_iterate(struct btrfs_fs_info *fs_info,
262 int (*check_func)(struct btrfs_fs_info *, u8 *, u8,
263 u64))
264{
265 struct btrfs_root *root = fs_info->uuid_root;
266 struct btrfs_key key;
267 struct btrfs_path *path;
268 int ret = 0;
269 struct extent_buffer *leaf;
270 int slot;
271 u32 item_size;
272 unsigned long offset;
273
274 path = btrfs_alloc_path();
275 if (!path) {
276 ret = -ENOMEM;
277 goto out;
278 }
279
280 key.objectid = 0;
281 key.type = 0;
282 key.offset = 0;
283
284again_search_slot:
285 ret = btrfs_search_forward(root, &key, path, 0);
286 if (ret) {
287 if (ret > 0)
288 ret = 0;
289 goto out;
290 }
291
292 while (1) {
293 cond_resched();
294 leaf = path->nodes[0];
295 slot = path->slots[0];
296 btrfs_item_key_to_cpu(leaf, &key, slot);
297
298 if (key.type != BTRFS_UUID_KEY_SUBVOL &&
299 key.type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
300 goto skip;
301
302 offset = btrfs_item_ptr_offset(leaf, slot);
303 item_size = btrfs_item_size_nr(leaf, slot);
304 if (!IS_ALIGNED(item_size, sizeof(u64))) {
305 btrfs_warn(fs_info,
306 "uuid item with illegal size %lu!",
307 (unsigned long)item_size);
308 goto skip;
309 }
310 while (item_size) {
311 u8 uuid[BTRFS_UUID_SIZE];
312 __le64 subid_le;
313 u64 subid_cpu;
314
315 put_unaligned_le64(key.objectid, uuid);
316 put_unaligned_le64(key.offset, uuid + sizeof(u64));
317 read_extent_buffer(leaf, &subid_le, offset,
318 sizeof(subid_le));
319 subid_cpu = le64_to_cpu(subid_le);
320 ret = check_func(fs_info, uuid, key.type, subid_cpu);
321 if (ret < 0)
322 goto out;
323 if (ret > 0) {
324 btrfs_release_path(path);
325 ret = btrfs_uuid_iter_rem(root, uuid, key.type,
326 subid_cpu);
327 if (ret == 0) {
328
329
330
331
332
333
334
335 goto again_search_slot;
336 }
337 if (ret < 0 && ret != -ENOENT)
338 goto out;
339 }
340 item_size -= sizeof(subid_le);
341 offset += sizeof(subid_le);
342 }
343
344skip:
345 ret = btrfs_next_item(root, path);
346 if (ret == 0)
347 continue;
348 else if (ret > 0)
349 ret = 0;
350 break;
351 }
352
353out:
354 btrfs_free_path(path);
355 return ret;
356}
357
