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1/*
2 * Copyright (C) 2011 Red Hat, Inc.
3 *
4 * This file is released under the GPL.
5 */
6
7#include "dm-space-map-common.h"
8#include "dm-space-map-disk.h"
9#include "dm-space-map.h"
10#include "dm-transaction-manager.h"
11
12#include <linux/list.h>
13#include <linux/slab.h>
14#include <linux/export.h>
15#include <linux/device-mapper.h>
16
17#define DM_MSG_PREFIX "space map disk"
18
19/*----------------------------------------------------------------*/
20
21/*
22 * Space map interface.
23 */
24struct sm_disk {
25 struct dm_space_map sm;
26
27 struct ll_disk ll;
28 struct ll_disk old_ll;
29
30 dm_block_t begin;
31 dm_block_t nr_allocated_this_transaction;
32};
33
34static void sm_disk_destroy(struct dm_space_map *sm)
35{
36 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
37
38 kfree(smd);
39}
40
41static int sm_disk_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
42{
43 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
44
45 return sm_ll_extend(&smd->ll, extra_blocks);
46}
47
48static int sm_disk_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count)
49{
50 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
51 *count = smd->old_ll.nr_blocks;
52
53 return 0;
54}
55
56static int sm_disk_get_nr_free(struct dm_space_map *sm, dm_block_t *count)
57{
58 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
59 *count = (smd->old_ll.nr_blocks - smd->old_ll.nr_allocated) - smd->nr_allocated_this_transaction;
60
61 return 0;
62}
63
64static int sm_disk_get_count(struct dm_space_map *sm, dm_block_t b,
65 uint32_t *result)
66{
67 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
68 return sm_ll_lookup(&smd->ll, b, result);
69}
70
71static int sm_disk_count_is_more_than_one(struct dm_space_map *sm, dm_block_t b,
72 int *result)
73{
74 int r;
75 uint32_t count;
76
77 r = sm_disk_get_count(sm, b, &count);
78 if (r)
79 return r;
80
81 *result = count > 1;
82
83 return 0;
84}
85
86static int sm_disk_set_count(struct dm_space_map *sm, dm_block_t b,
87 uint32_t count)
88{
89 int r;
90 uint32_t old_count;
91 enum allocation_event ev;
92 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
93
94 r = sm_ll_insert(&smd->ll, b, count, &ev);
95 if (!r) {
96 switch (ev) {
97 case SM_NONE:
98 break;
99
100 case SM_ALLOC:
101 /*
102 * This _must_ be free in the prior transaction
103 * otherwise we've lost atomicity.
104 */
105 smd->nr_allocated_this_transaction++;
106 break;
107
108 case SM_FREE:
109 /*
110 * It's only free if it's also free in the last
111 * transaction.
112 */
113 r = sm_ll_lookup(&smd->old_ll, b, &old_count);
114 if (r)
115 return r;
116
117 if (!old_count)
118 smd->nr_allocated_this_transaction--;
119 break;
120 }
121 }
122
123 return r;
124}
125
126static int sm_disk_inc_block(struct dm_space_map *sm, dm_block_t b)
127{
128 int r;
129 enum allocation_event ev;
130 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
131
132 r = sm_ll_inc(&smd->ll, b, &ev);
133 if (!r && (ev == SM_ALLOC))
134 /*
135 * This _must_ be free in the prior transaction
136 * otherwise we've lost atomicity.
137 */
138 smd->nr_allocated_this_transaction++;
139
140 return r;
141}
142
143static int sm_disk_dec_block(struct dm_space_map *sm, dm_block_t b)
144{
145 int r;
146 uint32_t old_count;
147 enum allocation_event ev;
148 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
149
150 r = sm_ll_dec(&smd->ll, b, &ev);
151 if (!r && (ev == SM_FREE)) {
152 /*
153 * It's only free if it's also free in the last
154 * transaction.
155 */
156 r = sm_ll_lookup(&smd->old_ll, b, &old_count);
157 if (!r && !old_count)
158 smd->nr_allocated_this_transaction--;
159 }
160
161 return r;
162}
163
164static int sm_disk_new_block(struct dm_space_map *sm, dm_block_t *b)
165{
166 int r;
167 enum allocation_event ev;
168 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
169
170 /*
171 * Any block we allocate has to be free in both the old and current ll.
172 */
173 r = sm_ll_find_common_free_block(&smd->old_ll, &smd->ll, smd->begin, smd->ll.nr_blocks, b);
174 if (r)
175 return r;
176
177 smd->begin = *b + 1;
178 r = sm_ll_inc(&smd->ll, *b, &ev);
179 if (!r) {
180 BUG_ON(ev != SM_ALLOC);
181 smd->nr_allocated_this_transaction++;
182 }
183
184 return r;
185}
186
187static int sm_disk_commit(struct dm_space_map *sm)
188{
189 int r;
190 dm_block_t nr_free;
191 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
192
193 r = sm_disk_get_nr_free(sm, &nr_free);
194 if (r)
195 return r;
196
197 r = sm_ll_commit(&smd->ll);
198 if (r)
199 return r;
200
201 memcpy(&smd->old_ll, &smd->ll, sizeof(smd->old_ll));
202 smd->begin = 0;
203 smd->nr_allocated_this_transaction = 0;
204
205 r = sm_disk_get_nr_free(sm, &nr_free);
206 if (r)
207 return r;
208
209 return 0;
210}
211
212static int sm_disk_root_size(struct dm_space_map *sm, size_t *result)
213{
214 *result = sizeof(struct disk_sm_root);
215
216 return 0;
217}
218
219static int sm_disk_copy_root(struct dm_space_map *sm, void *where_le, size_t max)
220{
221 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
222 struct disk_sm_root root_le;
223
224 root_le.nr_blocks = cpu_to_le64(smd->ll.nr_blocks);
225 root_le.nr_allocated = cpu_to_le64(smd->ll.nr_allocated);
226 root_le.bitmap_root = cpu_to_le64(smd->ll.bitmap_root);
227 root_le.ref_count_root = cpu_to_le64(smd->ll.ref_count_root);
228
229 if (max < sizeof(root_le))
230 return -ENOSPC;
231
232 memcpy(where_le, &root_le, sizeof(root_le));
233
234 return 0;
235}
236
237/*----------------------------------------------------------------*/
238
239static struct dm_space_map ops = {
240 .destroy = sm_disk_destroy,
241 .extend = sm_disk_extend,
242 .get_nr_blocks = sm_disk_get_nr_blocks,
243 .get_nr_free = sm_disk_get_nr_free,
244 .get_count = sm_disk_get_count,
245 .count_is_more_than_one = sm_disk_count_is_more_than_one,
246 .set_count = sm_disk_set_count,
247 .inc_block = sm_disk_inc_block,
248 .dec_block = sm_disk_dec_block,
249 .new_block = sm_disk_new_block,
250 .commit = sm_disk_commit,
251 .root_size = sm_disk_root_size,
252 .copy_root = sm_disk_copy_root,
253 .register_threshold_callback = NULL
254};
255
256struct dm_space_map *dm_sm_disk_create(struct dm_transaction_manager *tm,
257 dm_block_t nr_blocks)
258{
259 int r;
260 struct sm_disk *smd;
261
262 smd = kmalloc(sizeof(*smd), GFP_KERNEL);
263 if (!smd)
264 return ERR_PTR(-ENOMEM);
265
266 smd->begin = 0;
267 smd->nr_allocated_this_transaction = 0;
268 memcpy(&smd->sm, &ops, sizeof(smd->sm));
269
270 r = sm_ll_new_disk(&smd->ll, tm);
271 if (r)
272 goto bad;
273
274 r = sm_ll_extend(&smd->ll, nr_blocks);
275 if (r)
276 goto bad;
277
278 r = sm_disk_commit(&smd->sm);
279 if (r)
280 goto bad;
281
282 return &smd->sm;
283
284bad:
285 kfree(smd);
286 return ERR_PTR(r);
287}
288EXPORT_SYMBOL_GPL(dm_sm_disk_create);
289
290struct dm_space_map *dm_sm_disk_open(struct dm_transaction_manager *tm,
291 void *root_le, size_t len)
292{
293 int r;
294 struct sm_disk *smd;
295
296 smd = kmalloc(sizeof(*smd), GFP_KERNEL);
297 if (!smd)
298 return ERR_PTR(-ENOMEM);
299
300 smd->begin = 0;
301 smd->nr_allocated_this_transaction = 0;
302 memcpy(&smd->sm, &ops, sizeof(smd->sm));
303
304 r = sm_ll_open_disk(&smd->ll, tm, root_le, len);
305 if (r)
306 goto bad;
307
308 r = sm_disk_commit(&smd->sm);
309 if (r)
310 goto bad;
311
312 return &smd->sm;
313
314bad:
315 kfree(smd);
316 return ERR_PTR(r);
317}
318EXPORT_SYMBOL_GPL(dm_sm_disk_open);
319
320/*----------------------------------------------------------------*/
1/*
2 * Copyright (C) 2011 Red Hat, Inc.
3 *
4 * This file is released under the GPL.
5 */
6
7#include "dm-space-map-common.h"
8#include "dm-space-map-disk.h"
9#include "dm-space-map.h"
10#include "dm-transaction-manager.h"
11
12#include <linux/list.h>
13#include <linux/slab.h>
14#include <linux/export.h>
15#include <linux/device-mapper.h>
16
17#define DM_MSG_PREFIX "space map disk"
18
19/*----------------------------------------------------------------*/
20
21/*
22 * Space map interface.
23 */
24struct sm_disk {
25 struct dm_space_map sm;
26
27 struct ll_disk ll;
28 struct ll_disk old_ll;
29
30 dm_block_t begin;
31 dm_block_t nr_allocated_this_transaction;
32};
33
34static void sm_disk_destroy(struct dm_space_map *sm)
35{
36 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
37
38 kfree(smd);
39}
40
41static int sm_disk_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
42{
43 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
44
45 return sm_ll_extend(&smd->ll, extra_blocks);
46}
47
48static int sm_disk_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count)
49{
50 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
51 *count = smd->old_ll.nr_blocks;
52
53 return 0;
54}
55
56static int sm_disk_get_nr_free(struct dm_space_map *sm, dm_block_t *count)
57{
58 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
59 *count = (smd->old_ll.nr_blocks - smd->old_ll.nr_allocated) - smd->nr_allocated_this_transaction;
60
61 return 0;
62}
63
64static int sm_disk_get_count(struct dm_space_map *sm, dm_block_t b,
65 uint32_t *result)
66{
67 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
68 return sm_ll_lookup(&smd->ll, b, result);
69}
70
71static int sm_disk_count_is_more_than_one(struct dm_space_map *sm, dm_block_t b,
72 int *result)
73{
74 int r;
75 uint32_t count;
76
77 r = sm_disk_get_count(sm, b, &count);
78 if (r)
79 return r;
80
81 return count > 1;
82}
83
84static int sm_disk_set_count(struct dm_space_map *sm, dm_block_t b,
85 uint32_t count)
86{
87 int r;
88 uint32_t old_count;
89 enum allocation_event ev;
90 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
91
92 r = sm_ll_insert(&smd->ll, b, count, &ev);
93 if (!r) {
94 switch (ev) {
95 case SM_NONE:
96 break;
97
98 case SM_ALLOC:
99 /*
100 * This _must_ be free in the prior transaction
101 * otherwise we've lost atomicity.
102 */
103 smd->nr_allocated_this_transaction++;
104 break;
105
106 case SM_FREE:
107 /*
108 * It's only free if it's also free in the last
109 * transaction.
110 */
111 r = sm_ll_lookup(&smd->old_ll, b, &old_count);
112 if (r)
113 return r;
114
115 if (!old_count)
116 smd->nr_allocated_this_transaction--;
117 break;
118 }
119 }
120
121 return r;
122}
123
124static int sm_disk_inc_block(struct dm_space_map *sm, dm_block_t b)
125{
126 int r;
127 enum allocation_event ev;
128 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
129
130 r = sm_ll_inc(&smd->ll, b, &ev);
131 if (!r && (ev == SM_ALLOC))
132 /*
133 * This _must_ be free in the prior transaction
134 * otherwise we've lost atomicity.
135 */
136 smd->nr_allocated_this_transaction++;
137
138 return r;
139}
140
141static int sm_disk_dec_block(struct dm_space_map *sm, dm_block_t b)
142{
143 enum allocation_event ev;
144 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
145
146 return sm_ll_dec(&smd->ll, b, &ev);
147}
148
149static int sm_disk_new_block(struct dm_space_map *sm, dm_block_t *b)
150{
151 int r;
152 enum allocation_event ev;
153 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
154
155 /* FIXME: we should loop round a couple of times */
156 r = sm_ll_find_free_block(&smd->old_ll, smd->begin, smd->old_ll.nr_blocks, b);
157 if (r)
158 return r;
159
160 smd->begin = *b + 1;
161 r = sm_ll_inc(&smd->ll, *b, &ev);
162 if (!r) {
163 BUG_ON(ev != SM_ALLOC);
164 smd->nr_allocated_this_transaction++;
165 }
166
167 return r;
168}
169
170static int sm_disk_commit(struct dm_space_map *sm)
171{
172 int r;
173 dm_block_t nr_free;
174 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
175
176 r = sm_disk_get_nr_free(sm, &nr_free);
177 if (r)
178 return r;
179
180 r = sm_ll_commit(&smd->ll);
181 if (r)
182 return r;
183
184 memcpy(&smd->old_ll, &smd->ll, sizeof(smd->old_ll));
185 smd->begin = 0;
186 smd->nr_allocated_this_transaction = 0;
187
188 r = sm_disk_get_nr_free(sm, &nr_free);
189 if (r)
190 return r;
191
192 return 0;
193}
194
195static int sm_disk_root_size(struct dm_space_map *sm, size_t *result)
196{
197 *result = sizeof(struct disk_sm_root);
198
199 return 0;
200}
201
202static int sm_disk_copy_root(struct dm_space_map *sm, void *where_le, size_t max)
203{
204 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
205 struct disk_sm_root root_le;
206
207 root_le.nr_blocks = cpu_to_le64(smd->ll.nr_blocks);
208 root_le.nr_allocated = cpu_to_le64(smd->ll.nr_allocated);
209 root_le.bitmap_root = cpu_to_le64(smd->ll.bitmap_root);
210 root_le.ref_count_root = cpu_to_le64(smd->ll.ref_count_root);
211
212 if (max < sizeof(root_le))
213 return -ENOSPC;
214
215 memcpy(where_le, &root_le, sizeof(root_le));
216
217 return 0;
218}
219
220/*----------------------------------------------------------------*/
221
222static struct dm_space_map ops = {
223 .destroy = sm_disk_destroy,
224 .extend = sm_disk_extend,
225 .get_nr_blocks = sm_disk_get_nr_blocks,
226 .get_nr_free = sm_disk_get_nr_free,
227 .get_count = sm_disk_get_count,
228 .count_is_more_than_one = sm_disk_count_is_more_than_one,
229 .set_count = sm_disk_set_count,
230 .inc_block = sm_disk_inc_block,
231 .dec_block = sm_disk_dec_block,
232 .new_block = sm_disk_new_block,
233 .commit = sm_disk_commit,
234 .root_size = sm_disk_root_size,
235 .copy_root = sm_disk_copy_root,
236 .register_threshold_callback = NULL
237};
238
239struct dm_space_map *dm_sm_disk_create(struct dm_transaction_manager *tm,
240 dm_block_t nr_blocks)
241{
242 int r;
243 struct sm_disk *smd;
244
245 smd = kmalloc(sizeof(*smd), GFP_KERNEL);
246 if (!smd)
247 return ERR_PTR(-ENOMEM);
248
249 smd->begin = 0;
250 smd->nr_allocated_this_transaction = 0;
251 memcpy(&smd->sm, &ops, sizeof(smd->sm));
252
253 r = sm_ll_new_disk(&smd->ll, tm);
254 if (r)
255 goto bad;
256
257 r = sm_ll_extend(&smd->ll, nr_blocks);
258 if (r)
259 goto bad;
260
261 r = sm_disk_commit(&smd->sm);
262 if (r)
263 goto bad;
264
265 return &smd->sm;
266
267bad:
268 kfree(smd);
269 return ERR_PTR(r);
270}
271EXPORT_SYMBOL_GPL(dm_sm_disk_create);
272
273struct dm_space_map *dm_sm_disk_open(struct dm_transaction_manager *tm,
274 void *root_le, size_t len)
275{
276 int r;
277 struct sm_disk *smd;
278
279 smd = kmalloc(sizeof(*smd), GFP_KERNEL);
280 if (!smd)
281 return ERR_PTR(-ENOMEM);
282
283 smd->begin = 0;
284 smd->nr_allocated_this_transaction = 0;
285 memcpy(&smd->sm, &ops, sizeof(smd->sm));
286
287 r = sm_ll_open_disk(&smd->ll, tm, root_le, len);
288 if (r)
289 goto bad;
290
291 r = sm_disk_commit(&smd->sm);
292 if (r)
293 goto bad;
294
295 return &smd->sm;
296
297bad:
298 kfree(smd);
299 return ERR_PTR(r);
300}
301EXPORT_SYMBOL_GPL(dm_sm_disk_open);
302
303/*----------------------------------------------------------------*/