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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) STRATO AG 2013. All rights reserved.
4 */
5
6#include <linux/uuid.h>
7#include <asm/unaligned.h>
8#include "messages.h"
9#include "ctree.h"
10#include "transaction.h"
11#include "disk-io.h"
12#include "print-tree.h"
13#include "fs.h"
14#include "accessors.h"
15#include "uuid-tree.h"
16
17static void btrfs_uuid_to_key(u8 *uuid, u8 type, struct btrfs_key *key)
18{
19 key->type = type;
20 key->objectid = get_unaligned_le64(uuid);
21 key->offset = get_unaligned_le64(uuid + sizeof(u64));
22}
23
24/* return -ENOENT for !found, < 0 for errors, or 0 if an item was found */
25static int btrfs_uuid_tree_lookup(struct btrfs_root *uuid_root, u8 *uuid,
26 u8 type, u64 subid)
27{
28 int ret;
29 struct btrfs_path *path = NULL;
30 struct extent_buffer *eb;
31 int slot;
32 u32 item_size;
33 unsigned long offset;
34 struct btrfs_key key;
35
36 if (WARN_ON_ONCE(!uuid_root)) {
37 ret = -ENOENT;
38 goto out;
39 }
40
41 path = btrfs_alloc_path();
42 if (!path) {
43 ret = -ENOMEM;
44 goto out;
45 }
46
47 btrfs_uuid_to_key(uuid, type, &key);
48 ret = btrfs_search_slot(NULL, uuid_root, &key, path, 0, 0);
49 if (ret < 0) {
50 goto out;
51 } else if (ret > 0) {
52 ret = -ENOENT;
53 goto out;
54 }
55
56 eb = path->nodes[0];
57 slot = path->slots[0];
58 item_size = btrfs_item_size(eb, slot);
59 offset = btrfs_item_ptr_offset(eb, slot);
60 ret = -ENOENT;
61
62 if (!IS_ALIGNED(item_size, sizeof(u64))) {
63 btrfs_warn(uuid_root->fs_info,
64 "uuid item with illegal size %lu!",
65 (unsigned long)item_size);
66 goto out;
67 }
68 while (item_size) {
69 __le64 data;
70
71 read_extent_buffer(eb, &data, offset, sizeof(data));
72 if (le64_to_cpu(data) == subid) {
73 ret = 0;
74 break;
75 }
76 offset += sizeof(data);
77 item_size -= sizeof(data);
78 }
79
80out:
81 btrfs_free_path(path);
82 return ret;
83}
84
85int btrfs_uuid_tree_add(struct btrfs_trans_handle *trans, u8 *uuid, u8 type,
86 u64 subid_cpu)
87{
88 struct btrfs_fs_info *fs_info = trans->fs_info;
89 struct btrfs_root *uuid_root = fs_info->uuid_root;
90 int ret;
91 struct btrfs_path *path = NULL;
92 struct btrfs_key key;
93 struct extent_buffer *eb;
94 int slot;
95 unsigned long offset;
96 __le64 subid_le;
97
98 ret = btrfs_uuid_tree_lookup(uuid_root, uuid, type, subid_cpu);
99 if (ret != -ENOENT)
100 return ret;
101
102 if (WARN_ON_ONCE(!uuid_root)) {
103 ret = -EINVAL;
104 goto out;
105 }
106
107 btrfs_uuid_to_key(uuid, type, &key);
108
109 path = btrfs_alloc_path();
110 if (!path) {
111 ret = -ENOMEM;
112 goto out;
113 }
114
115 ret = btrfs_insert_empty_item(trans, uuid_root, path, &key,
116 sizeof(subid_le));
117 if (ret >= 0) {
118 /* Add an item for the type for the first time */
119 eb = path->nodes[0];
120 slot = path->slots[0];
121 offset = btrfs_item_ptr_offset(eb, slot);
122 } else if (ret == -EEXIST) {
123 /*
124 * An item with that type already exists.
125 * Extend the item and store the new subid at the end.
126 */
127 btrfs_extend_item(path, sizeof(subid_le));
128 eb = path->nodes[0];
129 slot = path->slots[0];
130 offset = btrfs_item_ptr_offset(eb, slot);
131 offset += btrfs_item_size(eb, slot) - sizeof(subid_le);
132 } else {
133 btrfs_warn(fs_info,
134 "insert uuid item failed %d (0x%016llx, 0x%016llx) type %u!",
135 ret, key.objectid, key.offset, type);
136 goto out;
137 }
138
139 ret = 0;
140 subid_le = cpu_to_le64(subid_cpu);
141 write_extent_buffer(eb, &subid_le, offset, sizeof(subid_le));
142 btrfs_mark_buffer_dirty(eb);
143
144out:
145 btrfs_free_path(path);
146 return ret;
147}
148
149int btrfs_uuid_tree_remove(struct btrfs_trans_handle *trans, u8 *uuid, u8 type,
150 u64 subid)
151{
152 struct btrfs_fs_info *fs_info = trans->fs_info;
153 struct btrfs_root *uuid_root = fs_info->uuid_root;
154 int ret;
155 struct btrfs_path *path = NULL;
156 struct btrfs_key key;
157 struct extent_buffer *eb;
158 int slot;
159 unsigned long offset;
160 u32 item_size;
161 unsigned long move_dst;
162 unsigned long move_src;
163 unsigned long move_len;
164
165 if (WARN_ON_ONCE(!uuid_root)) {
166 ret = -EINVAL;
167 goto out;
168 }
169
170 btrfs_uuid_to_key(uuid, type, &key);
171
172 path = btrfs_alloc_path();
173 if (!path) {
174 ret = -ENOMEM;
175 goto out;
176 }
177
178 ret = btrfs_search_slot(trans, uuid_root, &key, path, -1, 1);
179 if (ret < 0) {
180 btrfs_warn(fs_info, "error %d while searching for uuid item!",
181 ret);
182 goto out;
183 }
184 if (ret > 0) {
185 ret = -ENOENT;
186 goto out;
187 }
188
189 eb = path->nodes[0];
190 slot = path->slots[0];
191 offset = btrfs_item_ptr_offset(eb, slot);
192 item_size = btrfs_item_size(eb, slot);
193 if (!IS_ALIGNED(item_size, sizeof(u64))) {
194 btrfs_warn(fs_info, "uuid item with illegal size %lu!",
195 (unsigned long)item_size);
196 ret = -ENOENT;
197 goto out;
198 }
199 while (item_size) {
200 __le64 read_subid;
201
202 read_extent_buffer(eb, &read_subid, offset, sizeof(read_subid));
203 if (le64_to_cpu(read_subid) == subid)
204 break;
205 offset += sizeof(read_subid);
206 item_size -= sizeof(read_subid);
207 }
208
209 if (!item_size) {
210 ret = -ENOENT;
211 goto out;
212 }
213
214 item_size = btrfs_item_size(eb, slot);
215 if (item_size == sizeof(subid)) {
216 ret = btrfs_del_item(trans, uuid_root, path);
217 goto out;
218 }
219
220 move_dst = offset;
221 move_src = offset + sizeof(subid);
222 move_len = item_size - (move_src - btrfs_item_ptr_offset(eb, slot));
223 memmove_extent_buffer(eb, move_dst, move_src, move_len);
224 btrfs_truncate_item(path, item_size - sizeof(subid), 1);
225
226out:
227 btrfs_free_path(path);
228 return ret;
229}
230
231static int btrfs_uuid_iter_rem(struct btrfs_root *uuid_root, u8 *uuid, u8 type,
232 u64 subid)
233{
234 struct btrfs_trans_handle *trans;
235 int ret;
236
237 /* 1 - for the uuid item */
238 trans = btrfs_start_transaction(uuid_root, 1);
239 if (IS_ERR(trans)) {
240 ret = PTR_ERR(trans);
241 goto out;
242 }
243
244 ret = btrfs_uuid_tree_remove(trans, uuid, type, subid);
245 btrfs_end_transaction(trans);
246
247out:
248 return ret;
249}
250
251/*
252 * Check if there's an matching subvolume for given UUID
253 *
254 * Return:
255 * 0 check succeeded, the entry is not outdated
256 * > 0 if the check failed, the caller should remove the entry
257 * < 0 if an error occurred
258 */
259static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,
260 u8 *uuid, u8 type, u64 subvolid)
261{
262 int ret = 0;
263 struct btrfs_root *subvol_root;
264
265 if (type != BTRFS_UUID_KEY_SUBVOL &&
266 type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
267 goto out;
268
269 subvol_root = btrfs_get_fs_root(fs_info, subvolid, true);
270 if (IS_ERR(subvol_root)) {
271 ret = PTR_ERR(subvol_root);
272 if (ret == -ENOENT)
273 ret = 1;
274 goto out;
275 }
276
277 switch (type) {
278 case BTRFS_UUID_KEY_SUBVOL:
279 if (memcmp(uuid, subvol_root->root_item.uuid, BTRFS_UUID_SIZE))
280 ret = 1;
281 break;
282 case BTRFS_UUID_KEY_RECEIVED_SUBVOL:
283 if (memcmp(uuid, subvol_root->root_item.received_uuid,
284 BTRFS_UUID_SIZE))
285 ret = 1;
286 break;
287 }
288 btrfs_put_root(subvol_root);
289out:
290 return ret;
291}
292
293int btrfs_uuid_tree_iterate(struct btrfs_fs_info *fs_info)
294{
295 struct btrfs_root *root = fs_info->uuid_root;
296 struct btrfs_key key;
297 struct btrfs_path *path;
298 int ret = 0;
299 struct extent_buffer *leaf;
300 int slot;
301 u32 item_size;
302 unsigned long offset;
303
304 path = btrfs_alloc_path();
305 if (!path) {
306 ret = -ENOMEM;
307 goto out;
308 }
309
310 key.objectid = 0;
311 key.type = 0;
312 key.offset = 0;
313
314again_search_slot:
315 ret = btrfs_search_forward(root, &key, path, BTRFS_OLDEST_GENERATION);
316 if (ret) {
317 if (ret > 0)
318 ret = 0;
319 goto out;
320 }
321
322 while (1) {
323 if (btrfs_fs_closing(fs_info)) {
324 ret = -EINTR;
325 goto out;
326 }
327 cond_resched();
328 leaf = path->nodes[0];
329 slot = path->slots[0];
330 btrfs_item_key_to_cpu(leaf, &key, slot);
331
332 if (key.type != BTRFS_UUID_KEY_SUBVOL &&
333 key.type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
334 goto skip;
335
336 offset = btrfs_item_ptr_offset(leaf, slot);
337 item_size = btrfs_item_size(leaf, slot);
338 if (!IS_ALIGNED(item_size, sizeof(u64))) {
339 btrfs_warn(fs_info,
340 "uuid item with illegal size %lu!",
341 (unsigned long)item_size);
342 goto skip;
343 }
344 while (item_size) {
345 u8 uuid[BTRFS_UUID_SIZE];
346 __le64 subid_le;
347 u64 subid_cpu;
348
349 put_unaligned_le64(key.objectid, uuid);
350 put_unaligned_le64(key.offset, uuid + sizeof(u64));
351 read_extent_buffer(leaf, &subid_le, offset,
352 sizeof(subid_le));
353 subid_cpu = le64_to_cpu(subid_le);
354 ret = btrfs_check_uuid_tree_entry(fs_info, uuid,
355 key.type, subid_cpu);
356 if (ret < 0)
357 goto out;
358 if (ret > 0) {
359 btrfs_release_path(path);
360 ret = btrfs_uuid_iter_rem(root, uuid, key.type,
361 subid_cpu);
362 if (ret == 0) {
363 /*
364 * this might look inefficient, but the
365 * justification is that it is an
366 * exception that check_func returns 1,
367 * and that in the regular case only one
368 * entry per UUID exists.
369 */
370 goto again_search_slot;
371 }
372 if (ret < 0 && ret != -ENOENT)
373 goto out;
374 key.offset++;
375 goto again_search_slot;
376 }
377 item_size -= sizeof(subid_le);
378 offset += sizeof(subid_le);
379 }
380
381skip:
382 ret = btrfs_next_item(root, path);
383 if (ret == 0)
384 continue;
385 else if (ret > 0)
386 ret = 0;
387 break;
388 }
389
390out:
391 btrfs_free_path(path);
392 return ret;
393}
1/*
2 * Copyright (C) STRATO AG 2013. All rights reserved.
3 *
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.
7 *
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.
12 *
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.
17 */
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/* return -ENOENT for !found, < 0 for errors, or 0 if an item was found */
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, "uuid item with illegal size %lu!",
73 (unsigned long)item_size);
74 goto out;
75 }
76 while (item_size) {
77 __le64 data;
78
79 read_extent_buffer(eb, &data, offset, sizeof(data));
80 if (le64_to_cpu(data) == subid) {
81 ret = 0;
82 break;
83 }
84 offset += sizeof(data);
85 item_size -= sizeof(data);
86 }
87
88out:
89 btrfs_free_path(path);
90 return ret;
91}
92
93int btrfs_uuid_tree_add(struct btrfs_trans_handle *trans,
94 struct btrfs_root *uuid_root, u8 *uuid, u8 type,
95 u64 subid_cpu)
96{
97 int ret;
98 struct btrfs_path *path = NULL;
99 struct btrfs_key key;
100 struct extent_buffer *eb;
101 int slot;
102 unsigned long offset;
103 __le64 subid_le;
104
105 ret = btrfs_uuid_tree_lookup(uuid_root, uuid, type, subid_cpu);
106 if (ret != -ENOENT)
107 return ret;
108
109 if (WARN_ON_ONCE(!uuid_root)) {
110 ret = -EINVAL;
111 goto out;
112 }
113
114 btrfs_uuid_to_key(uuid, type, &key);
115
116 path = btrfs_alloc_path();
117 if (!path) {
118 ret = -ENOMEM;
119 goto out;
120 }
121
122 ret = btrfs_insert_empty_item(trans, uuid_root, path, &key,
123 sizeof(subid_le));
124 if (ret >= 0) {
125 /* Add an item for the type for the first time */
126 eb = path->nodes[0];
127 slot = path->slots[0];
128 offset = btrfs_item_ptr_offset(eb, slot);
129 } else if (ret == -EEXIST) {
130 /*
131 * An item with that type already exists.
132 * Extend the item and store the new subid at the end.
133 */
134 btrfs_extend_item(uuid_root, path, sizeof(subid_le));
135 eb = path->nodes[0];
136 slot = path->slots[0];
137 offset = btrfs_item_ptr_offset(eb, slot);
138 offset += btrfs_item_size_nr(eb, slot) - sizeof(subid_le);
139 } else if (ret < 0) {
140 btrfs_warn(uuid_root->fs_info, "insert uuid item failed %d "
141 "(0x%016llx, 0x%016llx) type %u!",
142 ret, (unsigned long long)key.objectid,
143 (unsigned long long)key.offset, type);
144 goto out;
145 }
146
147 ret = 0;
148 subid_le = cpu_to_le64(subid_cpu);
149 write_extent_buffer(eb, &subid_le, offset, sizeof(subid_le));
150 btrfs_mark_buffer_dirty(eb);
151
152out:
153 btrfs_free_path(path);
154 return ret;
155}
156
157int btrfs_uuid_tree_rem(struct btrfs_trans_handle *trans,
158 struct btrfs_root *uuid_root, u8 *uuid, u8 type,
159 u64 subid)
160{
161 int ret;
162 struct btrfs_path *path = NULL;
163 struct btrfs_key key;
164 struct extent_buffer *eb;
165 int slot;
166 unsigned long offset;
167 u32 item_size;
168 unsigned long move_dst;
169 unsigned long move_src;
170 unsigned long move_len;
171
172 if (WARN_ON_ONCE(!uuid_root)) {
173 ret = -EINVAL;
174 goto out;
175 }
176
177 btrfs_uuid_to_key(uuid, type, &key);
178
179 path = btrfs_alloc_path();
180 if (!path) {
181 ret = -ENOMEM;
182 goto out;
183 }
184
185 ret = btrfs_search_slot(trans, uuid_root, &key, path, -1, 1);
186 if (ret < 0) {
187 btrfs_warn(uuid_root->fs_info, "error %d while searching for uuid item!",
188 ret);
189 goto out;
190 }
191 if (ret > 0) {
192 ret = -ENOENT;
193 goto out;
194 }
195
196 eb = path->nodes[0];
197 slot = path->slots[0];
198 offset = btrfs_item_ptr_offset(eb, slot);
199 item_size = btrfs_item_size_nr(eb, slot);
200 if (!IS_ALIGNED(item_size, sizeof(u64))) {
201 btrfs_warn(uuid_root->fs_info, "uuid item with illegal size %lu!",
202 (unsigned long)item_size);
203 ret = -ENOENT;
204 goto out;
205 }
206 while (item_size) {
207 __le64 read_subid;
208
209 read_extent_buffer(eb, &read_subid, offset, sizeof(read_subid));
210 if (le64_to_cpu(read_subid) == subid)
211 break;
212 offset += sizeof(read_subid);
213 item_size -= sizeof(read_subid);
214 }
215
216 if (!item_size) {
217 ret = -ENOENT;
218 goto out;
219 }
220
221 item_size = btrfs_item_size_nr(eb, slot);
222 if (item_size == sizeof(subid)) {
223 ret = btrfs_del_item(trans, uuid_root, path);
224 goto out;
225 }
226
227 move_dst = offset;
228 move_src = offset + sizeof(subid);
229 move_len = item_size - (move_src - btrfs_item_ptr_offset(eb, slot));
230 memmove_extent_buffer(eb, move_dst, move_src, move_len);
231 btrfs_truncate_item(uuid_root, path, item_size - sizeof(subid), 1);
232
233out:
234 btrfs_free_path(path);
235 return ret;
236}
237
238static int btrfs_uuid_iter_rem(struct btrfs_root *uuid_root, u8 *uuid, u8 type,
239 u64 subid)
240{
241 struct btrfs_trans_handle *trans;
242 int ret;
243
244 /* 1 - for the uuid item */
245 trans = btrfs_start_transaction(uuid_root, 1);
246 if (IS_ERR(trans)) {
247 ret = PTR_ERR(trans);
248 goto out;
249 }
250
251 ret = btrfs_uuid_tree_rem(trans, uuid_root, uuid, type, subid);
252 btrfs_end_transaction(trans, uuid_root);
253
254out:
255 return ret;
256}
257
258int btrfs_uuid_tree_iterate(struct btrfs_fs_info *fs_info,
259 int (*check_func)(struct btrfs_fs_info *, u8 *, u8,
260 u64))
261{
262 struct btrfs_root *root = fs_info->uuid_root;
263 struct btrfs_key key;
264 struct btrfs_path *path;
265 int ret = 0;
266 struct extent_buffer *leaf;
267 int slot;
268 u32 item_size;
269 unsigned long offset;
270
271 path = btrfs_alloc_path();
272 if (!path) {
273 ret = -ENOMEM;
274 goto out;
275 }
276
277 key.objectid = 0;
278 key.type = 0;
279 key.offset = 0;
280
281again_search_slot:
282 ret = btrfs_search_forward(root, &key, path, 0);
283 if (ret) {
284 if (ret > 0)
285 ret = 0;
286 goto out;
287 }
288
289 while (1) {
290 cond_resched();
291 leaf = path->nodes[0];
292 slot = path->slots[0];
293 btrfs_item_key_to_cpu(leaf, &key, slot);
294
295 if (key.type != BTRFS_UUID_KEY_SUBVOL &&
296 key.type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
297 goto skip;
298
299 offset = btrfs_item_ptr_offset(leaf, slot);
300 item_size = btrfs_item_size_nr(leaf, slot);
301 if (!IS_ALIGNED(item_size, sizeof(u64))) {
302 btrfs_warn(fs_info, "uuid item with illegal size %lu!",
303 (unsigned long)item_size);
304 goto skip;
305 }
306 while (item_size) {
307 u8 uuid[BTRFS_UUID_SIZE];
308 __le64 subid_le;
309 u64 subid_cpu;
310
311 put_unaligned_le64(key.objectid, uuid);
312 put_unaligned_le64(key.offset, uuid + sizeof(u64));
313 read_extent_buffer(leaf, &subid_le, offset,
314 sizeof(subid_le));
315 subid_cpu = le64_to_cpu(subid_le);
316 ret = check_func(fs_info, uuid, key.type, subid_cpu);
317 if (ret < 0)
318 goto out;
319 if (ret > 0) {
320 btrfs_release_path(path);
321 ret = btrfs_uuid_iter_rem(root, uuid, key.type,
322 subid_cpu);
323 if (ret == 0) {
324 /*
325 * this might look inefficient, but the
326 * justification is that it is an
327 * exception that check_func returns 1,
328 * and that in the regular case only one
329 * entry per UUID exists.
330 */
331 goto again_search_slot;
332 }
333 if (ret < 0 && ret != -ENOENT)
334 goto out;
335 }
336 item_size -= sizeof(subid_le);
337 offset += sizeof(subid_le);
338 }
339
340skip:
341 ret = btrfs_next_item(root, path);
342 if (ret == 0)
343 continue;
344 else if (ret > 0)
345 ret = 0;
346 break;
347 }
348
349out:
350 btrfs_free_path(path);
351 if (ret)
352 btrfs_warn(fs_info, "btrfs_uuid_tree_iterate failed %d", ret);
353 return 0;
354}