Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2010 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 17 | #include "ext4_utils.h" |
| 18 | #include "allocate.h" |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 19 | |
Colin Cross | dc5abee | 2012-04-23 23:20:48 -0700 | [diff] [blame] | 20 | #include <sparse/sparse.h> |
| 21 | |
Colin Cross | 33f96c6 | 2010-12-22 18:40:14 -0800 | [diff] [blame] | 22 | #include <stdio.h> |
| 23 | #include <stdlib.h> |
| 24 | |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 25 | struct region { |
| 26 | u32 block; |
| 27 | u32 len; |
| 28 | int bg; |
| 29 | struct region *next; |
| 30 | struct region *prev; |
| 31 | }; |
| 32 | |
| 33 | struct block_group_info { |
| 34 | u32 first_block; |
| 35 | int header_blocks; |
| 36 | int data_blocks_used; |
| 37 | int has_superblock; |
| 38 | u8 *bitmaps; |
| 39 | u8 *block_bitmap; |
| 40 | u8 *inode_bitmap; |
| 41 | u8 *inode_table; |
| 42 | u32 free_blocks; |
| 43 | u32 first_free_block; |
| 44 | u32 free_inodes; |
| 45 | u32 first_free_inode; |
| 46 | u16 flags; |
| 47 | u16 used_dirs; |
| 48 | }; |
| 49 | |
Nick Kralevich | 4df62f3 | 2013-02-07 14:21:34 -0800 | [diff] [blame] | 50 | struct xattr_list_element { |
| 51 | struct ext4_inode *inode; |
| 52 | struct ext4_xattr_header *header; |
| 53 | struct xattr_list_element *next; |
| 54 | }; |
| 55 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 56 | struct block_allocation *create_allocation() |
| 57 | { |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 58 | struct block_allocation *alloc = malloc(sizeof(struct block_allocation)); |
| 59 | alloc->list.first = NULL; |
| 60 | alloc->list.last = NULL; |
| 61 | alloc->oob_list.first = NULL; |
| 62 | alloc->oob_list.last = NULL; |
| 63 | alloc->list.iter = NULL; |
| 64 | alloc->list.partial_iter = 0; |
| 65 | alloc->oob_list.iter = NULL; |
| 66 | alloc->oob_list.partial_iter = 0; |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 67 | alloc->filename = NULL; |
| 68 | alloc->next = NULL; |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 69 | return alloc; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 70 | } |
| 71 | |
Nick Kralevich | 4df62f3 | 2013-02-07 14:21:34 -0800 | [diff] [blame] | 72 | static struct ext4_xattr_header *xattr_list_find(struct ext4_inode *inode) |
| 73 | { |
| 74 | struct xattr_list_element *element; |
| 75 | for (element = aux_info.xattrs; element != NULL; element = element->next) { |
| 76 | if (element->inode == inode) |
| 77 | return element->header; |
| 78 | } |
| 79 | return NULL; |
| 80 | } |
| 81 | |
| 82 | static void xattr_list_insert(struct ext4_inode *inode, struct ext4_xattr_header *header) |
| 83 | { |
| 84 | struct xattr_list_element *element = malloc(sizeof(struct xattr_list_element)); |
| 85 | element->inode = inode; |
| 86 | element->header = header; |
| 87 | element->next = aux_info.xattrs; |
| 88 | aux_info.xattrs = element; |
| 89 | } |
| 90 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 91 | static void region_list_remove(struct region_list *list, struct region *reg) |
| 92 | { |
| 93 | if (reg->prev) |
| 94 | reg->prev->next = reg->next; |
| 95 | |
| 96 | if (reg->next) |
| 97 | reg->next->prev = reg->prev; |
| 98 | |
| 99 | if (list->first == reg) |
| 100 | list->first = reg->next; |
| 101 | |
| 102 | if (list->last == reg) |
| 103 | list->last = reg->prev; |
| 104 | |
| 105 | reg->next = NULL; |
| 106 | reg->prev = NULL; |
| 107 | } |
| 108 | |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 109 | static void region_list_append(struct region_list *list, struct region *reg) |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 110 | { |
| 111 | if (list->first == NULL) { |
| 112 | list->first = reg; |
| 113 | list->last = reg; |
| 114 | list->iter = reg; |
| 115 | list->partial_iter = 0; |
| 116 | reg->prev = NULL; |
| 117 | } else { |
| 118 | list->last->next = reg; |
| 119 | reg->prev = list->last; |
| 120 | list->last = reg; |
| 121 | } |
| 122 | reg->next = NULL; |
| 123 | } |
| 124 | |
| 125 | #if 0 |
| 126 | static void dump_starting_from(struct region *reg) |
| 127 | { |
| 128 | for (; reg; reg = reg->next) { |
| 129 | printf("%p: Blocks %d-%d (%d)\n", reg, |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 130 | reg->block, reg->block + reg->len - 1, reg->len) |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 131 | } |
| 132 | } |
| 133 | |
| 134 | static void dump_region_lists(struct block_allocation *alloc) { |
| 135 | |
| 136 | printf("Main list:\n"); |
| 137 | dump_starting_from(alloc->list.first); |
| 138 | |
| 139 | printf("OOB list:\n"); |
| 140 | dump_starting_from(alloc->oob_list.first); |
| 141 | } |
| 142 | #endif |
| 143 | |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 144 | void print_blocks(FILE* f, struct block_allocation *alloc) |
| 145 | { |
| 146 | struct region *reg; |
| 147 | for (reg = alloc->list.first; reg; reg = reg->next) { |
| 148 | if (reg->len == 1) { |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 149 | fprintf(f, " %d", reg->block); |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 150 | } else { |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 151 | fprintf(f, " %d-%d", reg->block, reg->block + reg->len - 1); |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 152 | } |
| 153 | } |
| 154 | fputc('\n', f); |
| 155 | } |
| 156 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 157 | void append_region(struct block_allocation *alloc, |
| 158 | u32 block, u32 len, int bg_num) |
| 159 | { |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 160 | struct region *reg; |
| 161 | reg = malloc(sizeof(struct region)); |
| 162 | reg->block = block; |
| 163 | reg->len = len; |
| 164 | reg->bg = bg_num; |
| 165 | reg->next = NULL; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 166 | |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 167 | region_list_append(&alloc->list, reg); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 168 | } |
| 169 | |
| 170 | static void allocate_bg_inode_table(struct block_group_info *bg) |
| 171 | { |
| 172 | if (bg->inode_table != NULL) |
| 173 | return; |
| 174 | |
| 175 | u32 block = bg->first_block + 2; |
| 176 | |
| 177 | if (bg->has_superblock) |
Colin Cross | 22742ce | 2010-12-22 16:01:52 -0800 | [diff] [blame] | 178 | block += aux_info.bg_desc_blocks + info.bg_desc_reserve_blocks + 1; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 179 | |
| 180 | bg->inode_table = calloc(aux_info.inode_table_blocks, info.block_size); |
| 181 | if (bg->inode_table == NULL) |
| 182 | critical_error_errno("calloc"); |
| 183 | |
Colin Cross | 782879a | 2014-01-23 13:08:16 -0800 | [diff] [blame] | 184 | sparse_file_add_data(ext4_sparse_file, bg->inode_table, |
Colin Cross | f0ee37f | 2012-04-24 17:48:43 -0700 | [diff] [blame] | 185 | aux_info.inode_table_blocks * info.block_size, block); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 186 | |
Colin Cross | 56497f2 | 2013-02-04 00:44:55 -0800 | [diff] [blame] | 187 | bg->flags &= ~EXT4_BG_INODE_UNINIT; |
Ken Sumrall | 107a9f1 | 2011-06-29 20:28:30 -0700 | [diff] [blame] | 188 | } |
| 189 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 190 | static int bitmap_set_bit(u8 *bitmap, u32 bit) |
| 191 | { |
| 192 | if (bitmap[bit / 8] & 1 << (bit % 8)) |
| 193 | return 1; |
| 194 | |
| 195 | bitmap[bit / 8] |= 1 << (bit % 8); |
| 196 | return 0; |
| 197 | } |
| 198 | |
| 199 | static int bitmap_set_8_bits(u8 *bitmap, u32 bit) |
| 200 | { |
| 201 | int ret = bitmap[bit / 8]; |
| 202 | bitmap[bit / 8] = 0xFF; |
| 203 | return ret; |
| 204 | } |
| 205 | |
| 206 | /* Marks a the first num_blocks blocks in a block group as used, and accounts |
| 207 | for them in the block group free block info. */ |
| 208 | static int reserve_blocks(struct block_group_info *bg, u32 start, u32 num) |
| 209 | { |
| 210 | unsigned int i = 0; |
| 211 | |
| 212 | u32 block = start; |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 213 | if (num > bg->free_blocks) |
| 214 | return -1; |
| 215 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 216 | for (i = 0; i < num && block % 8 != 0; i++, block++) { |
| 217 | if (bitmap_set_bit(bg->block_bitmap, block)) { |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 218 | error("attempted to reserve already reserved block"); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 219 | return -1; |
| 220 | } |
| 221 | } |
| 222 | |
| 223 | for (; i + 8 <= (num & ~7); i += 8, block += 8) { |
| 224 | if (bitmap_set_8_bits(bg->block_bitmap, block)) { |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 225 | error("attempted to reserve already reserved block"); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 226 | return -1; |
| 227 | } |
| 228 | } |
| 229 | |
| 230 | for (; i < num; i++, block++) { |
| 231 | if (bitmap_set_bit(bg->block_bitmap, block)) { |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 232 | error("attempted to reserve already reserved block"); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 233 | return -1; |
| 234 | } |
| 235 | } |
| 236 | |
| 237 | bg->free_blocks -= num; |
| 238 | if (start == bg->first_free_block) |
| 239 | bg->first_free_block = start + num; |
| 240 | |
| 241 | return 0; |
| 242 | } |
| 243 | |
| 244 | static void free_blocks(struct block_group_info *bg, u32 num_blocks) |
| 245 | { |
| 246 | unsigned int i; |
| 247 | u32 block = bg->first_free_block - 1; |
| 248 | for (i = 0; i < num_blocks; i++, block--) |
| 249 | bg->block_bitmap[block / 8] &= ~(1 << (block % 8)); |
| 250 | bg->free_blocks += num_blocks; |
| 251 | bg->first_free_block -= num_blocks; |
| 252 | } |
| 253 | |
| 254 | /* Reduces an existing allocation by len blocks by return the last blocks |
| 255 | to the free pool in their block group. Assumes that the blocks being |
| 256 | returned were the last ones allocated out of the block group */ |
| 257 | void reduce_allocation(struct block_allocation *alloc, u32 len) |
| 258 | { |
| 259 | while (len) { |
| 260 | struct region *last_reg = alloc->list.last; |
| 261 | |
| 262 | if (last_reg->len > len) { |
| 263 | free_blocks(&aux_info.bgs[last_reg->bg], len); |
| 264 | last_reg->len -= len; |
| 265 | len = 0; |
| 266 | } else { |
Colin Cross | a1a175a | 2010-06-17 17:27:20 -0700 | [diff] [blame] | 267 | struct region *reg = alloc->list.last->prev; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 268 | free_blocks(&aux_info.bgs[last_reg->bg], last_reg->len); |
| 269 | len -= last_reg->len; |
Colin Cross | a1a175a | 2010-06-17 17:27:20 -0700 | [diff] [blame] | 270 | if (reg) { |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 271 | reg->next = NULL; |
Colin Cross | a1a175a | 2010-06-17 17:27:20 -0700 | [diff] [blame] | 272 | } else { |
| 273 | alloc->list.first = NULL; |
| 274 | alloc->list.last = NULL; |
| 275 | alloc->list.iter = NULL; |
| 276 | alloc->list.partial_iter = 0; |
| 277 | } |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 278 | free(last_reg); |
| 279 | } |
| 280 | } |
| 281 | } |
| 282 | |
| 283 | static void init_bg(struct block_group_info *bg, unsigned int i) |
| 284 | { |
| 285 | int header_blocks = 2 + aux_info.inode_table_blocks; |
| 286 | |
| 287 | bg->has_superblock = ext4_bg_has_super_block(i); |
| 288 | |
| 289 | if (bg->has_superblock) |
Colin Cross | 22742ce | 2010-12-22 16:01:52 -0800 | [diff] [blame] | 290 | header_blocks += 1 + aux_info.bg_desc_blocks + info.bg_desc_reserve_blocks; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 291 | |
| 292 | bg->bitmaps = calloc(info.block_size, 2); |
| 293 | bg->block_bitmap = bg->bitmaps; |
| 294 | bg->inode_bitmap = bg->bitmaps + info.block_size; |
| 295 | |
| 296 | bg->header_blocks = header_blocks; |
| 297 | bg->first_block = aux_info.first_data_block + i * info.blocks_per_group; |
| 298 | |
| 299 | u32 block = bg->first_block; |
| 300 | if (bg->has_superblock) |
Colin Cross | 22742ce | 2010-12-22 16:01:52 -0800 | [diff] [blame] | 301 | block += 1 + aux_info.bg_desc_blocks + info.bg_desc_reserve_blocks; |
Colin Cross | 782879a | 2014-01-23 13:08:16 -0800 | [diff] [blame] | 302 | sparse_file_add_data(ext4_sparse_file, bg->bitmaps, 2 * info.block_size, |
Colin Cross | f0ee37f | 2012-04-24 17:48:43 -0700 | [diff] [blame] | 303 | block); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 304 | |
| 305 | bg->data_blocks_used = 0; |
| 306 | bg->free_blocks = info.blocks_per_group; |
| 307 | bg->first_free_block = 0; |
| 308 | bg->free_inodes = info.inodes_per_group; |
| 309 | bg->first_free_inode = 1; |
Theodore Ts'o | 468e700 | 2015-09-09 12:26:53 -0400 | [diff] [blame] | 310 | bg->flags = 0; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 311 | |
| 312 | if (reserve_blocks(bg, bg->first_free_block, bg->header_blocks) < 0) |
| 313 | error("failed to reserve %u blocks in block group %u\n", bg->header_blocks, i); |
| 314 | |
Ken Sumrall | 17de654 | 2013-08-15 19:06:29 -0700 | [diff] [blame] | 315 | if (bg->first_block + info.blocks_per_group > aux_info.len_blocks) { |
| 316 | u32 overrun = bg->first_block + info.blocks_per_group - aux_info.len_blocks; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 317 | reserve_blocks(bg, info.blocks_per_group - overrun, overrun); |
Ken Sumrall | 17de654 | 2013-08-15 19:06:29 -0700 | [diff] [blame] | 318 | } |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 319 | } |
| 320 | |
| 321 | void block_allocator_init() |
| 322 | { |
| 323 | unsigned int i; |
| 324 | |
| 325 | aux_info.bgs = calloc(sizeof(struct block_group_info), aux_info.groups); |
| 326 | if (aux_info.bgs == NULL) |
| 327 | critical_error_errno("calloc"); |
| 328 | |
| 329 | for (i = 0; i < aux_info.groups; i++) |
| 330 | init_bg(&aux_info.bgs[i], i); |
| 331 | } |
| 332 | |
| 333 | void block_allocator_free() |
| 334 | { |
| 335 | unsigned int i; |
| 336 | |
| 337 | for (i = 0; i < aux_info.groups; i++) { |
| 338 | free(aux_info.bgs[i].bitmaps); |
| 339 | free(aux_info.bgs[i].inode_table); |
| 340 | } |
| 341 | free(aux_info.bgs); |
| 342 | } |
| 343 | |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 344 | static u32 ext4_allocate_blocks_from_block_group(u32 len, int bg_num) |
| 345 | { |
| 346 | if (get_free_blocks(bg_num) < len) |
| 347 | return EXT4_ALLOCATE_FAILED; |
| 348 | |
| 349 | u32 block = aux_info.bgs[bg_num].first_free_block; |
| 350 | struct block_group_info *bg = &aux_info.bgs[bg_num]; |
| 351 | if (reserve_blocks(bg, bg->first_free_block, len) < 0) { |
| 352 | error("failed to reserve %u blocks in block group %u\n", len, bg_num); |
| 353 | return EXT4_ALLOCATE_FAILED; |
| 354 | } |
| 355 | |
| 356 | aux_info.bgs[bg_num].data_blocks_used += len; |
| 357 | |
| 358 | return bg->first_block + block; |
| 359 | } |
| 360 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 361 | /* Allocate a single block and return its block number */ |
| 362 | u32 allocate_block() |
| 363 | { |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 364 | unsigned int i; |
| 365 | for (i = 0; i < aux_info.groups; i++) { |
| 366 | u32 block = ext4_allocate_blocks_from_block_group(1, i); |
| 367 | |
| 368 | if (block != EXT4_ALLOCATE_FAILED) |
| 369 | return block; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 370 | } |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 371 | |
| 372 | return EXT4_ALLOCATE_FAILED; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 373 | } |
| 374 | |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 375 | static struct region *ext4_allocate_best_fit_partial(u32 len) |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 376 | { |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 377 | unsigned int i; |
| 378 | unsigned int found_bg = 0; |
| 379 | u32 found_bg_len = 0; |
| 380 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 381 | for (i = 0; i < aux_info.groups; i++) { |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 382 | u32 bg_len = aux_info.bgs[i].free_blocks; |
| 383 | |
| 384 | if ((len <= bg_len && (found_bg_len == 0 || bg_len < found_bg_len)) || |
| 385 | (len > found_bg_len && bg_len > found_bg_len)) { |
| 386 | found_bg = i; |
| 387 | found_bg_len = bg_len; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 388 | } |
| 389 | } |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 390 | |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 391 | if (found_bg_len) { |
| 392 | u32 allocate_len = min(len, found_bg_len); |
| 393 | struct region *reg; |
| 394 | u32 block = ext4_allocate_blocks_from_block_group(allocate_len, found_bg); |
| 395 | if (block == EXT4_ALLOCATE_FAILED) { |
| 396 | error("failed to allocate %d blocks in block group %d", allocate_len, found_bg); |
| 397 | return NULL; |
| 398 | } |
| 399 | reg = malloc(sizeof(struct region)); |
| 400 | reg->block = block; |
| 401 | reg->len = allocate_len; |
| 402 | reg->next = NULL; |
| 403 | reg->prev = NULL; |
| 404 | reg->bg = found_bg; |
| 405 | return reg; |
| 406 | } else { |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 407 | error("failed to allocate %u blocks, out of space?", len); |
| 408 | } |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 409 | |
| 410 | return NULL; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 411 | } |
| 412 | |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 413 | static struct region *ext4_allocate_best_fit(u32 len) |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 414 | { |
| 415 | struct region *first_reg = NULL; |
| 416 | struct region *prev_reg = NULL; |
| 417 | struct region *reg; |
| 418 | |
| 419 | while (len > 0) { |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 420 | reg = ext4_allocate_best_fit_partial(len); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 421 | if (reg == NULL) |
| 422 | return NULL; |
| 423 | |
| 424 | if (first_reg == NULL) |
| 425 | first_reg = reg; |
| 426 | |
| 427 | if (prev_reg) { |
| 428 | prev_reg->next = reg; |
| 429 | reg->prev = prev_reg; |
| 430 | } |
| 431 | |
| 432 | prev_reg = reg; |
| 433 | len -= reg->len; |
| 434 | } |
| 435 | |
| 436 | return first_reg; |
| 437 | } |
| 438 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 439 | /* Allocate len blocks. The blocks may be spread across multiple block groups, |
| 440 | and are returned in a linked list of the blocks in each block group. The |
| 441 | allocation algorithm is: |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame^] | 442 | 1. If the remaining allocation is larger than any available contiguous region, |
| 443 | allocate the largest contiguous region and loop |
| 444 | 2. Otherwise, allocate the smallest contiguous region that it fits in |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 445 | */ |
| 446 | struct block_allocation *allocate_blocks(u32 len) |
| 447 | { |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 448 | struct region *reg = ext4_allocate_best_fit(len); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 449 | |
| 450 | if (reg == NULL) |
| 451 | return NULL; |
| 452 | |
| 453 | struct block_allocation *alloc = create_allocation(); |
| 454 | alloc->list.first = reg; |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 455 | alloc->list.last = reg; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 456 | alloc->list.iter = alloc->list.first; |
| 457 | alloc->list.partial_iter = 0; |
| 458 | return alloc; |
| 459 | } |
| 460 | |
| 461 | /* Returns the number of discontiguous regions used by an allocation */ |
| 462 | int block_allocation_num_regions(struct block_allocation *alloc) |
| 463 | { |
| 464 | unsigned int i; |
| 465 | struct region *reg = alloc->list.first; |
| 466 | |
| 467 | for (i = 0; reg != NULL; reg = reg->next) |
| 468 | i++; |
| 469 | |
| 470 | return i; |
| 471 | } |
| 472 | |
| 473 | int block_allocation_len(struct block_allocation *alloc) |
| 474 | { |
| 475 | unsigned int i; |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 476 | struct region *reg = alloc->list.first; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 477 | |
| 478 | for (i = 0; reg != NULL; reg = reg->next) |
| 479 | i += reg->len; |
| 480 | |
| 481 | return i; |
| 482 | } |
| 483 | |
| 484 | /* Returns the block number of the block'th block in an allocation */ |
| 485 | u32 get_block(struct block_allocation *alloc, u32 block) |
| 486 | { |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 487 | struct region *reg = alloc->list.iter; |
| 488 | block += alloc->list.partial_iter; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 489 | |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 490 | for (; reg; reg = reg->next) { |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 491 | if (block < reg->len) |
| 492 | return reg->block + block; |
| 493 | block -= reg->len; |
| 494 | } |
| 495 | return EXT4_ALLOCATE_FAILED; |
| 496 | } |
| 497 | |
| 498 | u32 get_oob_block(struct block_allocation *alloc, u32 block) |
| 499 | { |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 500 | struct region *reg = alloc->oob_list.iter; |
| 501 | block += alloc->oob_list.partial_iter; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 502 | |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 503 | for (; reg; reg = reg->next) { |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 504 | if (block < reg->len) |
| 505 | return reg->block + block; |
| 506 | block -= reg->len; |
| 507 | } |
| 508 | return EXT4_ALLOCATE_FAILED; |
| 509 | } |
| 510 | |
| 511 | /* Gets the starting block and length in blocks of the first region |
| 512 | of an allocation */ |
| 513 | void get_region(struct block_allocation *alloc, u32 *block, u32 *len) |
| 514 | { |
| 515 | *block = alloc->list.iter->block; |
| 516 | *len = alloc->list.iter->len - alloc->list.partial_iter; |
| 517 | } |
| 518 | |
| 519 | /* Move to the next region in an allocation */ |
| 520 | void get_next_region(struct block_allocation *alloc) |
| 521 | { |
| 522 | alloc->list.iter = alloc->list.iter->next; |
| 523 | alloc->list.partial_iter = 0; |
| 524 | } |
| 525 | |
| 526 | /* Returns the number of free blocks in a block group */ |
| 527 | u32 get_free_blocks(u32 bg) |
| 528 | { |
| 529 | return aux_info.bgs[bg].free_blocks; |
| 530 | } |
| 531 | |
| 532 | int last_region(struct block_allocation *alloc) |
| 533 | { |
| 534 | return (alloc->list.iter == NULL); |
| 535 | } |
| 536 | |
| 537 | void rewind_alloc(struct block_allocation *alloc) |
| 538 | { |
| 539 | alloc->list.iter = alloc->list.first; |
| 540 | alloc->list.partial_iter = 0; |
| 541 | } |
| 542 | |
| 543 | static struct region *do_split_allocation(struct block_allocation *alloc, u32 len) |
| 544 | { |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 545 | struct region *reg = alloc->list.iter; |
| 546 | struct region *new; |
| 547 | struct region *tmp; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 548 | |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 549 | while (reg && len >= reg->len) { |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 550 | len -= reg->len; |
| 551 | reg = reg->next; |
| 552 | } |
| 553 | |
| 554 | if (reg == NULL && len > 0) |
| 555 | return NULL; |
| 556 | |
| 557 | if (len > 0) { |
| 558 | new = malloc(sizeof(struct region)); |
| 559 | |
| 560 | new->bg = reg->bg; |
| 561 | new->block = reg->block + len; |
| 562 | new->len = reg->len - len; |
| 563 | new->next = reg->next; |
| 564 | new->prev = reg; |
| 565 | |
| 566 | reg->next = new; |
| 567 | reg->len = len; |
| 568 | |
| 569 | tmp = alloc->list.iter; |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 570 | alloc->list.iter = new; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 571 | return tmp; |
| 572 | } else { |
| 573 | return reg; |
| 574 | } |
| 575 | } |
| 576 | |
| 577 | /* Splits an allocation into two allocations. The returned allocation will |
| 578 | point to the first half, and the original allocation ptr will point to the |
| 579 | second half. */ |
| 580 | static struct region *split_allocation(struct block_allocation *alloc, u32 len) |
| 581 | { |
| 582 | /* First make sure there is a split at the current ptr */ |
| 583 | do_split_allocation(alloc, alloc->list.partial_iter); |
| 584 | |
| 585 | /* Then split off len blocks */ |
| 586 | struct region *middle = do_split_allocation(alloc, len); |
| 587 | alloc->list.partial_iter = 0; |
| 588 | return middle; |
| 589 | } |
| 590 | |
| 591 | /* Reserve the next blocks for oob data (indirect or extent blocks) */ |
| 592 | int reserve_oob_blocks(struct block_allocation *alloc, int blocks) |
| 593 | { |
| 594 | struct region *oob = split_allocation(alloc, blocks); |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 595 | struct region *next; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 596 | |
| 597 | if (oob == NULL) |
| 598 | return -1; |
| 599 | |
| 600 | while (oob && oob != alloc->list.iter) { |
| 601 | next = oob->next; |
| 602 | region_list_remove(&alloc->list, oob); |
| 603 | region_list_append(&alloc->oob_list, oob); |
| 604 | oob = next; |
| 605 | } |
| 606 | |
| 607 | return 0; |
| 608 | } |
| 609 | |
| 610 | static int advance_list_ptr(struct region_list *list, int blocks) |
| 611 | { |
| 612 | struct region *reg = list->iter; |
| 613 | |
| 614 | while (reg != NULL && blocks > 0) { |
| 615 | if (reg->len > list->partial_iter + blocks) { |
| 616 | list->partial_iter += blocks; |
| 617 | return 0; |
| 618 | } |
| 619 | |
| 620 | blocks -= (reg->len - list->partial_iter); |
| 621 | list->partial_iter = 0; |
| 622 | reg = reg->next; |
| 623 | } |
| 624 | |
| 625 | if (blocks > 0) |
| 626 | return -1; |
| 627 | |
| 628 | return 0; |
| 629 | } |
| 630 | |
| 631 | /* Move the allocation pointer forward */ |
| 632 | int advance_blocks(struct block_allocation *alloc, int blocks) |
| 633 | { |
| 634 | return advance_list_ptr(&alloc->list, blocks); |
| 635 | } |
| 636 | |
| 637 | int advance_oob_blocks(struct block_allocation *alloc, int blocks) |
| 638 | { |
| 639 | return advance_list_ptr(&alloc->oob_list, blocks); |
| 640 | } |
| 641 | |
| 642 | int append_oob_allocation(struct block_allocation *alloc, u32 len) |
| 643 | { |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 644 | struct region *reg = ext4_allocate_best_fit(len); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 645 | |
| 646 | if (reg == NULL) { |
| 647 | error("failed to allocate %d blocks", len); |
| 648 | return -1; |
| 649 | } |
| 650 | |
| 651 | for (; reg; reg = reg->next) |
| 652 | region_list_append(&alloc->oob_list, reg); |
| 653 | |
| 654 | return 0; |
| 655 | } |
| 656 | |
| 657 | /* Returns an ext4_inode structure for an inode number */ |
| 658 | struct ext4_inode *get_inode(u32 inode) |
| 659 | { |
| 660 | inode -= 1; |
| 661 | int bg = inode / info.inodes_per_group; |
| 662 | inode %= info.inodes_per_group; |
| 663 | |
| 664 | allocate_bg_inode_table(&aux_info.bgs[bg]); |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 665 | return (struct ext4_inode *)(aux_info.bgs[bg].inode_table + inode * |
| 666 | info.inode_size); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 667 | } |
| 668 | |
Nick Kralevich | 4df62f3 | 2013-02-07 14:21:34 -0800 | [diff] [blame] | 669 | struct ext4_xattr_header *get_xattr_block_for_inode(struct ext4_inode *inode) |
| 670 | { |
| 671 | struct ext4_xattr_header *block = xattr_list_find(inode); |
| 672 | if (block != NULL) |
| 673 | return block; |
| 674 | |
| 675 | u32 block_num = allocate_block(); |
| 676 | block = calloc(info.block_size, 1); |
| 677 | if (block == NULL) { |
| 678 | error("get_xattr: failed to allocate %d", info.block_size); |
| 679 | return NULL; |
| 680 | } |
| 681 | |
| 682 | block->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
| 683 | block->h_refcount = cpu_to_le32(1); |
| 684 | block->h_blocks = cpu_to_le32(1); |
| 685 | inode->i_blocks_lo = cpu_to_le32(le32_to_cpu(inode->i_blocks_lo) + (info.block_size / 512)); |
| 686 | inode->i_file_acl_lo = cpu_to_le32(block_num); |
| 687 | |
Colin Cross | 782879a | 2014-01-23 13:08:16 -0800 | [diff] [blame] | 688 | int result = sparse_file_add_data(ext4_sparse_file, block, info.block_size, block_num); |
Nick Kralevich | 4df62f3 | 2013-02-07 14:21:34 -0800 | [diff] [blame] | 689 | if (result != 0) { |
| 690 | error("get_xattr: sparse_file_add_data failure %d", result); |
| 691 | free(block); |
| 692 | return NULL; |
| 693 | } |
| 694 | xattr_list_insert(inode, block); |
| 695 | return block; |
| 696 | } |
| 697 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 698 | /* Mark the first len inodes in a block group as used */ |
| 699 | u32 reserve_inodes(int bg, u32 num) |
| 700 | { |
| 701 | unsigned int i; |
| 702 | u32 inode; |
| 703 | |
| 704 | if (get_free_inodes(bg) < num) |
| 705 | return EXT4_ALLOCATE_FAILED; |
| 706 | |
| 707 | for (i = 0; i < num; i++) { |
| 708 | inode = aux_info.bgs[bg].first_free_inode + i - 1; |
| 709 | aux_info.bgs[bg].inode_bitmap[inode / 8] |= 1 << (inode % 8); |
| 710 | } |
| 711 | |
| 712 | inode = aux_info.bgs[bg].first_free_inode; |
| 713 | |
| 714 | aux_info.bgs[bg].first_free_inode += num; |
| 715 | aux_info.bgs[bg].free_inodes -= num; |
| 716 | |
| 717 | return inode; |
| 718 | } |
| 719 | |
| 720 | /* Returns the first free inode number |
| 721 | TODO: Inodes should be allocated in the block group of the data? */ |
| 722 | u32 allocate_inode() |
| 723 | { |
| 724 | unsigned int bg; |
| 725 | u32 inode; |
| 726 | |
| 727 | for (bg = 0; bg < aux_info.groups; bg++) { |
| 728 | inode = reserve_inodes(bg, 1); |
| 729 | if (inode != EXT4_ALLOCATE_FAILED) |
| 730 | return bg * info.inodes_per_group + inode; |
| 731 | } |
| 732 | |
| 733 | return EXT4_ALLOCATE_FAILED; |
| 734 | } |
| 735 | |
| 736 | /* Returns the number of free inodes in a block group */ |
| 737 | u32 get_free_inodes(u32 bg) |
| 738 | { |
| 739 | return aux_info.bgs[bg].free_inodes; |
| 740 | } |
| 741 | |
| 742 | /* Increments the directory count of the block group that contains inode */ |
| 743 | void add_directory(u32 inode) |
| 744 | { |
| 745 | int bg = (inode - 1) / info.inodes_per_group; |
| 746 | aux_info.bgs[bg].used_dirs += 1; |
| 747 | } |
| 748 | |
| 749 | /* Returns the number of inodes in a block group that are directories */ |
| 750 | u16 get_directories(int bg) |
| 751 | { |
| 752 | return aux_info.bgs[bg].used_dirs; |
| 753 | } |
| 754 | |
Colin Cross | 56497f2 | 2013-02-04 00:44:55 -0800 | [diff] [blame] | 755 | /* Returns the flags for a block group */ |
| 756 | u16 get_bg_flags(int bg) |
| 757 | { |
| 758 | return aux_info.bgs[bg].flags; |
| 759 | } |
| 760 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 761 | /* Frees the memory used by a linked list of allocation regions */ |
| 762 | void free_alloc(struct block_allocation *alloc) |
| 763 | { |
| 764 | struct region *reg; |
| 765 | |
| 766 | reg = alloc->list.first; |
| 767 | while (reg) { |
| 768 | struct region *next = reg->next; |
| 769 | free(reg); |
| 770 | reg = next; |
| 771 | } |
| 772 | |
| 773 | reg = alloc->oob_list.first; |
| 774 | while (reg) { |
| 775 | struct region *next = reg->next; |
| 776 | free(reg); |
| 777 | reg = next; |
| 778 | } |
| 779 | |
| 780 | free(alloc); |
| 781 | } |