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 */
25 struct 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
sm_disk_destroy(struct dm_space_map * sm)35 static 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(smd);
40 }
41
sm_disk_extend(struct dm_space_map * sm,dm_block_t extra_blocks)42 static 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(&smd->ll, extra_blocks);
47 }
48
sm_disk_get_nr_blocks(struct dm_space_map * sm,dm_block_t * count)49 static 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
sm_disk_get_nr_free(struct dm_space_map * sm,dm_block_t * count)58 static 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
sm_disk_get_count(struct dm_space_map * sm,dm_block_t b,uint32_t * result)67 static 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(&smd->ll, b, result);
73 }
74
sm_disk_count_is_more_than_one(struct dm_space_map * sm,dm_block_t b,int * result)75 static 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, &count);
82 if (r)
83 return r;
84
85 *result = count > 1;
86
87 return 0;
88 }
89
sm_disk_set_count(struct dm_space_map * sm,dm_block_t b,uint32_t count)90 static 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(&smd->ll, b, count, &nr_allocations);
98 if (!r)
99 smd->nr_allocated_this_transaction += nr_allocations;
100
101 return r;
102 }
103
sm_disk_inc_blocks(struct dm_space_map * sm,dm_block_t b,dm_block_t e)104 static 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(&smd->ll, b, e, &nr_allocations);
111 if (!r)
112 smd->nr_allocated_this_transaction += nr_allocations;
113
114 return r;
115 }
116
sm_disk_dec_blocks(struct dm_space_map * sm,dm_block_t b,dm_block_t e)117 static 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(&smd->ll, b, e, &nr_allocations);
124 if (!r)
125 smd->nr_allocated_this_transaction += nr_allocations;
126
127 return r;
128 }
129
sm_disk_new_block(struct dm_space_map * sm,dm_block_t * b)130 static 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(&smd->old_ll, &smd->ll, smd->begin, smd->ll.nr_blocks, 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(&smd->old_ll, &smd->ll, 0, smd->begin, b);
146
147 if (r)
148 return r;
149
150 smd->begin = *b + 1;
151 r = sm_ll_inc(&smd->ll, *b, *b + 1, &nr_allocations);
152 if (!r)
153 smd->nr_allocated_this_transaction += nr_allocations;
154
155 return r;
156 }
157
sm_disk_commit(struct dm_space_map * sm)158 static 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(&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
sm_disk_root_size(struct dm_space_map * sm,size_t * result)173 static 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
sm_disk_copy_root(struct dm_space_map * sm,void * where_le,size_t max)180 static 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
200 static 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
dm_sm_disk_create(struct dm_transaction_manager * tm,dm_block_t nr_blocks)217 struct 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(-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(&smd->ll, tm);
232 if (r)
233 goto bad;
234
235 r = sm_ll_extend(&smd->ll, nr_blocks);
236 if (r)
237 goto bad;
238
239 r = sm_disk_commit(&smd->sm);
240 if (r)
241 goto bad;
242
243 return &smd->sm;
244
245 bad:
246 kfree(smd);
247 return ERR_PTR(r);
248 }
249 EXPORT_SYMBOL_GPL(dm_sm_disk_create);
250
dm_sm_disk_open(struct dm_transaction_manager * tm,void * root_le,size_t len)251 struct 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(-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(&smd->ll, tm, root_le, len);
266 if (r)
267 goto bad;
268
269 r = sm_disk_commit(&smd->sm);
270 if (r)
271 goto bad;
272
273 return &smd->sm;
274
275 bad:
276 kfree(smd);
277 return ERR_PTR(r);
278 }
279 EXPORT_SYMBOL_GPL(dm_sm_disk_open);
280
281 /*----------------------------------------------------------------*/
282