2 * Copyright (C) 2011 Red Hat, Inc.
4 * This file is released under the GPL.
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"
12 #include <linux/list.h>
13 #include <linux/slab.h>
14 #include <linux/export.h>
15 #include <linux/device-mapper.h>
17 #define DM_MSG_PREFIX "space map disk"
19 /*----------------------------------------------------------------*/
22 * Space map interface.
25 struct dm_space_map sm;
28 struct ll_disk old_ll;
31 dm_block_t nr_allocated_this_transaction;
34 static void sm_disk_destroy(struct dm_space_map *sm)
36 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
41 static int sm_disk_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
43 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
45 return sm_ll_extend(&smd->ll, extra_blocks);
48 static int sm_disk_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count)
50 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
51 *count = smd->old_ll.nr_blocks;
56 static int sm_disk_get_nr_free(struct dm_space_map *sm, dm_block_t *count)
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;
64 static int sm_disk_get_count(struct dm_space_map *sm, dm_block_t b,
67 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
68 return sm_ll_lookup(&smd->ll, b, result);
71 static int sm_disk_count_is_more_than_one(struct dm_space_map *sm, dm_block_t b,
77 r = sm_disk_get_count(sm, b, &count);
86 static int sm_disk_set_count(struct dm_space_map *sm, dm_block_t b,
91 enum allocation_event ev;
92 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
94 r = sm_ll_insert(&smd->ll, b, count, &ev);
102 * This _must_ be free in the prior transaction
103 * otherwise we've lost atomicity.
105 smd->nr_allocated_this_transaction++;
110 * It's only free if it's also free in the last
113 r = sm_ll_lookup(&smd->old_ll, b, &old_count);
118 smd->nr_allocated_this_transaction--;
126 static int sm_disk_inc_block(struct dm_space_map *sm, dm_block_t b)
129 enum allocation_event ev;
130 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
132 r = sm_ll_inc(&smd->ll, b, &ev);
133 if (!r && (ev == SM_ALLOC))
135 * This _must_ be free in the prior transaction
136 * otherwise we've lost atomicity.
138 smd->nr_allocated_this_transaction++;
143 static int sm_disk_dec_block(struct dm_space_map *sm, dm_block_t b)
145 enum allocation_event ev;
146 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
148 return sm_ll_dec(&smd->ll, b, &ev);
151 static int sm_disk_new_block(struct dm_space_map *sm, dm_block_t *b)
154 enum allocation_event ev;
155 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
157 /* FIXME: we should loop round a couple of times */
158 r = sm_ll_find_free_block(&smd->old_ll, smd->begin, smd->old_ll.nr_blocks, b);
163 r = sm_ll_inc(&smd->ll, *b, &ev);
165 BUG_ON(ev != SM_ALLOC);
166 smd->nr_allocated_this_transaction++;
172 static int sm_disk_commit(struct dm_space_map *sm)
176 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
178 r = sm_disk_get_nr_free(sm, &nr_free);
182 r = sm_ll_commit(&smd->ll);
186 memcpy(&smd->old_ll, &smd->ll, sizeof(smd->old_ll));
188 smd->nr_allocated_this_transaction = 0;
190 r = sm_disk_get_nr_free(sm, &nr_free);
197 static int sm_disk_root_size(struct dm_space_map *sm, size_t *result)
199 *result = sizeof(struct disk_sm_root);
204 static int sm_disk_copy_root(struct dm_space_map *sm, void *where_le, size_t max)
206 struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
207 struct disk_sm_root root_le;
209 root_le.nr_blocks = cpu_to_le64(smd->ll.nr_blocks);
210 root_le.nr_allocated = cpu_to_le64(smd->ll.nr_allocated);
211 root_le.bitmap_root = cpu_to_le64(smd->ll.bitmap_root);
212 root_le.ref_count_root = cpu_to_le64(smd->ll.ref_count_root);
214 if (max < sizeof(root_le))
217 memcpy(where_le, &root_le, sizeof(root_le));
222 /*----------------------------------------------------------------*/
224 static struct dm_space_map ops = {
225 .destroy = sm_disk_destroy,
226 .extend = sm_disk_extend,
227 .get_nr_blocks = sm_disk_get_nr_blocks,
228 .get_nr_free = sm_disk_get_nr_free,
229 .get_count = sm_disk_get_count,
230 .count_is_more_than_one = sm_disk_count_is_more_than_one,
231 .set_count = sm_disk_set_count,
232 .inc_block = sm_disk_inc_block,
233 .dec_block = sm_disk_dec_block,
234 .new_block = sm_disk_new_block,
235 .commit = sm_disk_commit,
236 .root_size = sm_disk_root_size,
237 .copy_root = sm_disk_copy_root,
238 .register_threshold_callback = NULL
241 struct dm_space_map *dm_sm_disk_create(struct dm_transaction_manager *tm,
242 dm_block_t nr_blocks)
247 smd = kmalloc(sizeof(*smd), GFP_KERNEL);
249 return ERR_PTR(-ENOMEM);
252 smd->nr_allocated_this_transaction = 0;
253 memcpy(&smd->sm, &ops, sizeof(smd->sm));
255 r = sm_ll_new_disk(&smd->ll, tm);
259 r = sm_ll_extend(&smd->ll, nr_blocks);
263 r = sm_disk_commit(&smd->sm);
273 EXPORT_SYMBOL_GPL(dm_sm_disk_create);
275 struct dm_space_map *dm_sm_disk_open(struct dm_transaction_manager *tm,
276 void *root_le, size_t len)
281 smd = kmalloc(sizeof(*smd), GFP_KERNEL);
283 return ERR_PTR(-ENOMEM);
286 smd->nr_allocated_this_transaction = 0;
287 memcpy(&smd->sm, &ops, sizeof(smd->sm));
289 r = sm_ll_open_disk(&smd->ll, tm, root_le, len);
293 r = sm_disk_commit(&smd->sm);
303 EXPORT_SYMBOL_GPL(dm_sm_disk_open);
305 /*----------------------------------------------------------------*/