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 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 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 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 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 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 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 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 } 103 104 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 } 116 117 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 } 129 130 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 } 157 158 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 } 172 173 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 } 179 180 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 }; 216 217 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); 250 251 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