1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2011 Red Hat, Inc.
4 *
5 * This file is released under the GPL.
6 */
7
8#include "dm-space-map-common.h"
9#include "dm-space-map-disk.h"
10#include "dm-space-map.h"
11#include "dm-transaction-manager.h"
12
13#include <linux/list.h>
14#include <linux/slab.h>
15#include <linux/export.h>
16#include <linux/device-mapper.h>
17
18#define DM_MSG_PREFIX "space map disk"
19
20/*----------------------------------------------------------------*/
21
22/*
23 * Space map interface.
24 */
25struct sm_disk {
26 struct dm_space_map sm;
27
28 struct ll_disk ll;
29 struct ll_disk old_ll;
30
31 dm_block_t begin;
32 dm_block_t nr_allocated_this_transaction;
33};
34
35static void sm_disk_destroy(struct dm_space_map *sm)
36{
37 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
38
39 kfree(objp: smd);
40}
41
42static int sm_disk_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
43{
44 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
45
46 return sm_ll_extend(ll: &smd->ll, extra_blocks);
47}
48
49static int sm_disk_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count)
50{
51 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
52
53 *count = smd->old_ll.nr_blocks;
54
55 return 0;
56}
57
58static int sm_disk_get_nr_free(struct dm_space_map *sm, dm_block_t *count)
59{
60 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
61
62 *count = (smd->old_ll.nr_blocks - smd->old_ll.nr_allocated) - smd->nr_allocated_this_transaction;
63
64 return 0;
65}
66
67static int sm_disk_get_count(struct dm_space_map *sm, dm_block_t b,
68 uint32_t *result)
69{
70 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
71
72 return sm_ll_lookup(ll: &smd->ll, b, result);
73}
74
75static int sm_disk_count_is_more_than_one(struct dm_space_map *sm, dm_block_t b,
76 int *result)
77{
78 int r;
79 uint32_t count;
80
81 r = sm_disk_get_count(sm, b, result: &count);
82 if (r)
83 return r;
84
85 *result = count > 1;
86
87 return 0;
88}
89
90static int sm_disk_set_count(struct dm_space_map *sm, dm_block_t b,
91 uint32_t count)
92{
93 int r;
94 int32_t nr_allocations;
95 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
96
97 r = sm_ll_insert(ll: &smd->ll, b, ref_count: count, nr_allocations: &nr_allocations);
98 if (!r)
99 smd->nr_allocated_this_transaction += nr_allocations;
100
101 return r;
102}
103
104static int sm_disk_inc_blocks(struct dm_space_map *sm, dm_block_t b, dm_block_t e)
105{
106 int r;
107 int32_t nr_allocations;
108 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
109
110 r = sm_ll_inc(ll: &smd->ll, b, e, nr_allocations: &nr_allocations);
111 if (!r)
112 smd->nr_allocated_this_transaction += nr_allocations;
113
114 return r;
115}
116
117static int sm_disk_dec_blocks(struct dm_space_map *sm, dm_block_t b, dm_block_t e)
118{
119 int r;
120 int32_t nr_allocations;
121 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
122
123 r = sm_ll_dec(ll: &smd->ll, b, e, nr_allocations: &nr_allocations);
124 if (!r)
125 smd->nr_allocated_this_transaction += nr_allocations;
126
127 return r;
128}
129
130static int sm_disk_new_block(struct dm_space_map *sm, dm_block_t *b)
131{
132 int r;
133 int32_t nr_allocations;
134 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
135
136 /*
137 * Any block we allocate has to be free in both the old and current ll.
138 */
139 r = sm_ll_find_common_free_block(old_ll: &smd->old_ll, new_ll: &smd->ll, begin: smd->begin, end: smd->ll.nr_blocks, result: b);
140 if (r == -ENOSPC)
141 /*
142 * There's no free block between smd->begin and the end of the metadata device.
143 * We search before smd->begin in case something has been freed.
144 */
145 r = sm_ll_find_common_free_block(old_ll: &smd->old_ll, new_ll: &smd->ll, begin: 0, end: smd->begin, result: b);
146
147 if (r)
148 return r;
149
150 smd->begin = *b + 1;
151 r = sm_ll_inc(ll: &smd->ll, b: *b, e: *b + 1, nr_allocations: &nr_allocations);
152 if (!r)
153 smd->nr_allocated_this_transaction += nr_allocations;
154
155 return r;
156}
157
158static int sm_disk_commit(struct dm_space_map *sm)
159{
160 int r;
161 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
162
163 r = sm_ll_commit(ll: &smd->ll);
164 if (r)
165 return r;
166
167 memcpy(&smd->old_ll, &smd->ll, sizeof(smd->old_ll));
168 smd->nr_allocated_this_transaction = 0;
169
170 return 0;
171}
172
173static int sm_disk_root_size(struct dm_space_map *sm, size_t *result)
174{
175 *result = sizeof(struct disk_sm_root);
176
177 return 0;
178}
179
180static int sm_disk_copy_root(struct dm_space_map *sm, void *where_le, size_t max)
181{
182 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
183 struct disk_sm_root root_le;
184
185 root_le.nr_blocks = cpu_to_le64(smd->ll.nr_blocks);
186 root_le.nr_allocated = cpu_to_le64(smd->ll.nr_allocated);
187 root_le.bitmap_root = cpu_to_le64(smd->ll.bitmap_root);
188 root_le.ref_count_root = cpu_to_le64(smd->ll.ref_count_root);
189
190 if (max < sizeof(root_le))
191 return -ENOSPC;
192
193 memcpy(where_le, &root_le, sizeof(root_le));
194
195 return 0;
196}
197
198/*----------------------------------------------------------------*/
199
200static struct dm_space_map ops = {
201 .destroy = sm_disk_destroy,
202 .extend = sm_disk_extend,
203 .get_nr_blocks = sm_disk_get_nr_blocks,
204 .get_nr_free = sm_disk_get_nr_free,
205 .get_count = sm_disk_get_count,
206 .count_is_more_than_one = sm_disk_count_is_more_than_one,
207 .set_count = sm_disk_set_count,
208 .inc_blocks = sm_disk_inc_blocks,
209 .dec_blocks = sm_disk_dec_blocks,
210 .new_block = sm_disk_new_block,
211 .commit = sm_disk_commit,
212 .root_size = sm_disk_root_size,
213 .copy_root = sm_disk_copy_root,
214 .register_threshold_callback = NULL
215};
216
217struct dm_space_map *dm_sm_disk_create(struct dm_transaction_manager *tm,
218 dm_block_t nr_blocks)
219{
220 int r;
221 struct sm_disk *smd;
222
223 smd = kmalloc(sizeof(*smd), GFP_KERNEL);
224 if (!smd)
225 return ERR_PTR(error: -ENOMEM);
226
227 smd->begin = 0;
228 smd->nr_allocated_this_transaction = 0;
229 memcpy(&smd->sm, &ops, sizeof(smd->sm));
230
231 r = sm_ll_new_disk(ll: &smd->ll, tm);
232 if (r)
233 goto bad;
234
235 r = sm_ll_extend(ll: &smd->ll, extra_blocks: nr_blocks);
236 if (r)
237 goto bad;
238
239 r = sm_disk_commit(sm: &smd->sm);
240 if (r)
241 goto bad;
242
243 return &smd->sm;
244
245bad:
246 kfree(objp: smd);
247 return ERR_PTR(error: r);
248}
249EXPORT_SYMBOL_GPL(dm_sm_disk_create);
250
251struct dm_space_map *dm_sm_disk_open(struct dm_transaction_manager *tm,
252 void *root_le, size_t len)
253{
254 int r;
255 struct sm_disk *smd;
256
257 smd = kmalloc(sizeof(*smd), GFP_KERNEL);
258 if (!smd)
259 return ERR_PTR(error: -ENOMEM);
260
261 smd->begin = 0;
262 smd->nr_allocated_this_transaction = 0;
263 memcpy(&smd->sm, &ops, sizeof(smd->sm));
264
265 r = sm_ll_open_disk(ll: &smd->ll, tm, root_le, len);
266 if (r)
267 goto bad;
268
269 r = sm_disk_commit(sm: &smd->sm);
270 if (r)
271 goto bad;
272
273 return &smd->sm;
274
275bad:
276 kfree(objp: smd);
277 return ERR_PTR(error: r);
278}
279EXPORT_SYMBOL_GPL(dm_sm_disk_open);
280
281/*----------------------------------------------------------------*/
282

source code of linux/drivers/md/persistent-data/dm-space-map-disk.c