2
* Copyright (C) 2011 Red Hat, Inc.
4
* This file is released under the GPL.
7
#include "dm-space-map-checker.h"
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"
13
#include <linux/list.h>
14
#include <linux/slab.h>
15
#include <linux/export.h>
16
#include <linux/device-mapper.h>
18
#define DM_MSG_PREFIX "space map disk"
20
/*----------------------------------------------------------------*/
23
* Space map interface.
26
struct dm_space_map sm;
29
struct ll_disk old_ll;
32
dm_block_t nr_allocated_this_transaction;
35
static void sm_disk_destroy(struct dm_space_map *sm)
37
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
42
static int sm_disk_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
44
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
46
return sm_ll_extend(&smd->ll, extra_blocks);
49
static int sm_disk_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count)
51
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
52
*count = smd->old_ll.nr_blocks;
57
static int sm_disk_get_nr_free(struct dm_space_map *sm, dm_block_t *count)
59
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
60
*count = (smd->old_ll.nr_blocks - smd->old_ll.nr_allocated) - smd->nr_allocated_this_transaction;
65
static int sm_disk_get_count(struct dm_space_map *sm, dm_block_t b,
68
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
69
return sm_ll_lookup(&smd->ll, b, result);
72
static int sm_disk_count_is_more_than_one(struct dm_space_map *sm, dm_block_t b,
78
r = sm_disk_get_count(sm, b, &count);
85
static int sm_disk_set_count(struct dm_space_map *sm, dm_block_t b,
90
enum allocation_event ev;
91
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
93
r = sm_ll_insert(&smd->ll, b, count, &ev);
101
* This _must_ be free in the prior transaction
102
* otherwise we've lost atomicity.
104
smd->nr_allocated_this_transaction++;
109
* It's only free if it's also free in the last
112
r = sm_ll_lookup(&smd->old_ll, b, &old_count);
117
smd->nr_allocated_this_transaction--;
125
static int sm_disk_inc_block(struct dm_space_map *sm, dm_block_t b)
128
enum allocation_event ev;
129
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
131
r = sm_ll_inc(&smd->ll, b, &ev);
132
if (!r && (ev == SM_ALLOC))
134
* This _must_ be free in the prior transaction
135
* otherwise we've lost atomicity.
137
smd->nr_allocated_this_transaction++;
142
static int sm_disk_dec_block(struct dm_space_map *sm, dm_block_t b)
146
enum allocation_event ev;
147
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
149
r = sm_ll_dec(&smd->ll, b, &ev);
150
if (!r && (ev == SM_FREE)) {
152
* It's only free if it's also free in the last
155
r = sm_ll_lookup(&smd->old_ll, b, &old_count);
160
smd->nr_allocated_this_transaction--;
166
static int sm_disk_new_block(struct dm_space_map *sm, dm_block_t *b)
169
enum allocation_event ev;
170
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
172
/* FIXME: we should loop round a couple of times */
173
r = sm_ll_find_free_block(&smd->old_ll, smd->begin, smd->old_ll.nr_blocks, b);
178
r = sm_ll_inc(&smd->ll, *b, &ev);
180
BUG_ON(ev != SM_ALLOC);
181
smd->nr_allocated_this_transaction++;
187
static int sm_disk_commit(struct dm_space_map *sm)
191
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
193
r = sm_disk_get_nr_free(sm, &nr_free);
197
r = sm_ll_commit(&smd->ll);
201
memcpy(&smd->old_ll, &smd->ll, sizeof(smd->old_ll));
203
smd->nr_allocated_this_transaction = 0;
205
r = sm_disk_get_nr_free(sm, &nr_free);
212
static int sm_disk_root_size(struct dm_space_map *sm, size_t *result)
214
*result = sizeof(struct disk_sm_root);
219
static int sm_disk_copy_root(struct dm_space_map *sm, void *where_le, size_t max)
221
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
222
struct disk_sm_root root_le;
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);
229
if (max < sizeof(root_le))
232
memcpy(where_le, &root_le, sizeof(root_le));
237
/*----------------------------------------------------------------*/
239
static 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
255
static struct dm_space_map *dm_sm_disk_create_real(
256
struct dm_transaction_manager *tm,
257
dm_block_t nr_blocks)
262
smd = kmalloc(sizeof(*smd), GFP_KERNEL);
264
return ERR_PTR(-ENOMEM);
267
smd->nr_allocated_this_transaction = 0;
268
memcpy(&smd->sm, &ops, sizeof(smd->sm));
270
r = sm_ll_new_disk(&smd->ll, tm);
274
r = sm_ll_extend(&smd->ll, nr_blocks);
278
r = sm_disk_commit(&smd->sm);
289
struct dm_space_map *dm_sm_disk_create(struct dm_transaction_manager *tm,
290
dm_block_t nr_blocks)
292
struct dm_space_map *sm = dm_sm_disk_create_real(tm, nr_blocks);
293
return dm_sm_checker_create_fresh(sm);
295
EXPORT_SYMBOL_GPL(dm_sm_disk_create);
297
static struct dm_space_map *dm_sm_disk_open_real(
298
struct dm_transaction_manager *tm,
299
void *root_le, size_t len)
304
smd = kmalloc(sizeof(*smd), GFP_KERNEL);
306
return ERR_PTR(-ENOMEM);
309
smd->nr_allocated_this_transaction = 0;
310
memcpy(&smd->sm, &ops, sizeof(smd->sm));
312
r = sm_ll_open_disk(&smd->ll, tm, root_le, len);
316
r = sm_disk_commit(&smd->sm);
327
struct dm_space_map *dm_sm_disk_open(struct dm_transaction_manager *tm,
328
void *root_le, size_t len)
330
return dm_sm_checker_create(
331
dm_sm_disk_open_real(tm, root_le, len));
333
EXPORT_SYMBOL_GPL(dm_sm_disk_open);
335
/*----------------------------------------------------------------*/