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 | 9579198 | 2016-02-20 03:46:00 +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 | |
Nick Kralevich | 4df62f3 | 2013-02-07 14:21:34 -0800 | [diff] [blame] | 25 | struct xattr_list_element { |
| 26 | struct ext4_inode *inode; |
| 27 | struct ext4_xattr_header *header; |
| 28 | struct xattr_list_element *next; |
| 29 | }; |
| 30 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 31 | struct block_allocation *create_allocation() |
| 32 | { |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 33 | struct block_allocation *alloc = malloc(sizeof(struct block_allocation)); |
| 34 | alloc->list.first = NULL; |
| 35 | alloc->list.last = NULL; |
| 36 | alloc->oob_list.first = NULL; |
| 37 | alloc->oob_list.last = NULL; |
| 38 | alloc->list.iter = NULL; |
| 39 | alloc->list.partial_iter = 0; |
| 40 | alloc->oob_list.iter = NULL; |
| 41 | alloc->oob_list.partial_iter = 0; |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 42 | alloc->filename = NULL; |
| 43 | alloc->next = NULL; |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 44 | return alloc; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 45 | } |
| 46 | |
Nick Kralevich | 4df62f3 | 2013-02-07 14:21:34 -0800 | [diff] [blame] | 47 | static struct ext4_xattr_header *xattr_list_find(struct ext4_inode *inode) |
| 48 | { |
| 49 | struct xattr_list_element *element; |
| 50 | for (element = aux_info.xattrs; element != NULL; element = element->next) { |
| 51 | if (element->inode == inode) |
| 52 | return element->header; |
| 53 | } |
| 54 | return NULL; |
| 55 | } |
| 56 | |
| 57 | static void xattr_list_insert(struct ext4_inode *inode, struct ext4_xattr_header *header) |
| 58 | { |
| 59 | struct xattr_list_element *element = malloc(sizeof(struct xattr_list_element)); |
| 60 | element->inode = inode; |
| 61 | element->header = header; |
| 62 | element->next = aux_info.xattrs; |
| 63 | aux_info.xattrs = element; |
| 64 | } |
| 65 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 66 | static void region_list_remove(struct region_list *list, struct region *reg) |
| 67 | { |
| 68 | if (reg->prev) |
| 69 | reg->prev->next = reg->next; |
| 70 | |
| 71 | if (reg->next) |
| 72 | reg->next->prev = reg->prev; |
| 73 | |
| 74 | if (list->first == reg) |
| 75 | list->first = reg->next; |
| 76 | |
| 77 | if (list->last == reg) |
| 78 | list->last = reg->prev; |
| 79 | |
| 80 | reg->next = NULL; |
| 81 | reg->prev = NULL; |
| 82 | } |
| 83 | |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 84 | void region_list_append(struct region_list *list, struct region *reg) |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 85 | { |
| 86 | if (list->first == NULL) { |
| 87 | list->first = reg; |
| 88 | list->last = reg; |
| 89 | list->iter = reg; |
| 90 | list->partial_iter = 0; |
| 91 | reg->prev = NULL; |
| 92 | } else { |
| 93 | list->last->next = reg; |
| 94 | reg->prev = list->last; |
| 95 | list->last = reg; |
| 96 | } |
| 97 | reg->next = NULL; |
| 98 | } |
| 99 | |
| 100 | #if 0 |
| 101 | static void dump_starting_from(struct region *reg) |
| 102 | { |
| 103 | for (; reg; reg = reg->next) { |
| 104 | printf("%p: Blocks %d-%d (%d)\n", reg, |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 105 | reg->block, reg->block + reg->len - 1, reg->len) |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 106 | } |
| 107 | } |
| 108 | |
| 109 | static void dump_region_lists(struct block_allocation *alloc) { |
| 110 | |
| 111 | printf("Main list:\n"); |
| 112 | dump_starting_from(alloc->list.first); |
| 113 | |
| 114 | printf("OOB list:\n"); |
| 115 | dump_starting_from(alloc->oob_list.first); |
| 116 | } |
| 117 | #endif |
| 118 | |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 119 | void print_blocks(FILE* f, struct block_allocation *alloc, char separator) |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 120 | { |
| 121 | struct region *reg; |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 122 | fputc(' ', f); |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 123 | for (reg = alloc->list.first; reg; reg = reg->next) { |
| 124 | if (reg->len == 1) { |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 125 | fprintf(f, "%d", reg->block); |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 126 | } else { |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 127 | fprintf(f, "%d-%d", reg->block, reg->block + reg->len - 1); |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 128 | } |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 129 | fputc(separator, f); |
Doug Zongker | bec598e | 2014-08-12 11:35:37 -0700 | [diff] [blame] | 130 | } |
| 131 | fputc('\n', f); |
| 132 | } |
| 133 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 134 | void append_region(struct block_allocation *alloc, |
| 135 | u32 block, u32 len, int bg_num) |
| 136 | { |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 137 | struct region *reg; |
| 138 | reg = malloc(sizeof(struct region)); |
| 139 | reg->block = block; |
| 140 | reg->len = len; |
| 141 | reg->bg = bg_num; |
| 142 | reg->next = NULL; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 143 | |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 144 | region_list_append(&alloc->list, reg); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 145 | } |
| 146 | |
| 147 | static void allocate_bg_inode_table(struct block_group_info *bg) |
| 148 | { |
| 149 | if (bg->inode_table != NULL) |
| 150 | return; |
| 151 | |
| 152 | u32 block = bg->first_block + 2; |
| 153 | |
| 154 | if (bg->has_superblock) |
Colin Cross | 22742ce | 2010-12-22 16:01:52 -0800 | [diff] [blame] | 155 | block += aux_info.bg_desc_blocks + info.bg_desc_reserve_blocks + 1; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 156 | |
| 157 | bg->inode_table = calloc(aux_info.inode_table_blocks, info.block_size); |
| 158 | if (bg->inode_table == NULL) |
| 159 | critical_error_errno("calloc"); |
| 160 | |
Colin Cross | 782879a | 2014-01-23 13:08:16 -0800 | [diff] [blame] | 161 | sparse_file_add_data(ext4_sparse_file, bg->inode_table, |
Colin Cross | f0ee37f | 2012-04-24 17:48:43 -0700 | [diff] [blame] | 162 | aux_info.inode_table_blocks * info.block_size, block); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 163 | |
Colin Cross | 56497f2 | 2013-02-04 00:44:55 -0800 | [diff] [blame] | 164 | bg->flags &= ~EXT4_BG_INODE_UNINIT; |
Ken Sumrall | 107a9f1 | 2011-06-29 20:28:30 -0700 | [diff] [blame] | 165 | } |
| 166 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 167 | static int bitmap_set_bit(u8 *bitmap, u32 bit) |
| 168 | { |
| 169 | if (bitmap[bit / 8] & 1 << (bit % 8)) |
| 170 | return 1; |
| 171 | |
| 172 | bitmap[bit / 8] |= 1 << (bit % 8); |
| 173 | return 0; |
| 174 | } |
| 175 | |
| 176 | static int bitmap_set_8_bits(u8 *bitmap, u32 bit) |
| 177 | { |
| 178 | int ret = bitmap[bit / 8]; |
| 179 | bitmap[bit / 8] = 0xFF; |
| 180 | return ret; |
| 181 | } |
| 182 | |
| 183 | /* Marks a the first num_blocks blocks in a block group as used, and accounts |
| 184 | for them in the block group free block info. */ |
Mohamad Ayyash | a6866eb | 2016-03-02 21:10:45 -0800 | [diff] [blame] | 185 | static int reserve_blocks(struct block_group_info *bg, u32 bg_num, u32 start, u32 num) |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 186 | { |
| 187 | unsigned int i = 0; |
| 188 | |
| 189 | u32 block = start; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 190 | for (i = 0; i < num && block % 8 != 0; i++, block++) { |
| 191 | if (bitmap_set_bit(bg->block_bitmap, block)) { |
Mohamad Ayyash | a6866eb | 2016-03-02 21:10:45 -0800 | [diff] [blame] | 192 | error("attempted to reserve already reserved block %d in block group %d", block, bg_num); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 193 | return -1; |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | for (; i + 8 <= (num & ~7); i += 8, block += 8) { |
| 198 | if (bitmap_set_8_bits(bg->block_bitmap, block)) { |
Mohamad Ayyash | a6866eb | 2016-03-02 21:10:45 -0800 | [diff] [blame] | 199 | error("attempted to reserve already reserved block %d in block group %d", block, bg_num); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 200 | return -1; |
| 201 | } |
| 202 | } |
| 203 | |
| 204 | for (; i < num; i++, block++) { |
| 205 | if (bitmap_set_bit(bg->block_bitmap, block)) { |
Mohamad Ayyash | a6866eb | 2016-03-02 21:10:45 -0800 | [diff] [blame] | 206 | error("attempted to reserve already reserved block %d in block group %d", block, bg_num); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 207 | return -1; |
| 208 | } |
| 209 | } |
| 210 | |
| 211 | bg->free_blocks -= num; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 212 | |
| 213 | return 0; |
| 214 | } |
| 215 | |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 216 | static void free_blocks(struct block_group_info *bg, u32 block, u32 num_blocks) |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 217 | { |
| 218 | unsigned int i; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 219 | for (i = 0; i < num_blocks; i++, block--) |
| 220 | bg->block_bitmap[block / 8] &= ~(1 << (block % 8)); |
| 221 | bg->free_blocks += num_blocks; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 222 | } |
| 223 | |
| 224 | /* Reduces an existing allocation by len blocks by return the last blocks |
| 225 | to the free pool in their block group. Assumes that the blocks being |
| 226 | returned were the last ones allocated out of the block group */ |
| 227 | void reduce_allocation(struct block_allocation *alloc, u32 len) |
| 228 | { |
| 229 | while (len) { |
| 230 | struct region *last_reg = alloc->list.last; |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 231 | struct block_group_info *bg = &aux_info.bgs[last_reg->bg]; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 232 | |
| 233 | if (last_reg->len > len) { |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 234 | free_blocks(bg, last_reg->block + last_reg->len - bg->first_block - 1, len); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 235 | last_reg->len -= len; |
| 236 | len = 0; |
| 237 | } else { |
Colin Cross | a1a175a | 2010-06-17 17:27:20 -0700 | [diff] [blame] | 238 | struct region *reg = alloc->list.last->prev; |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 239 | free_blocks(bg, last_reg->block + last_reg->len - bg->first_block - 1, last_reg->len); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 240 | len -= last_reg->len; |
Colin Cross | a1a175a | 2010-06-17 17:27:20 -0700 | [diff] [blame] | 241 | if (reg) { |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 242 | reg->next = NULL; |
Colin Cross | a1a175a | 2010-06-17 17:27:20 -0700 | [diff] [blame] | 243 | } else { |
| 244 | alloc->list.first = NULL; |
| 245 | alloc->list.last = NULL; |
| 246 | alloc->list.iter = NULL; |
| 247 | alloc->list.partial_iter = 0; |
| 248 | } |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 249 | free(last_reg); |
| 250 | } |
| 251 | } |
| 252 | } |
| 253 | |
| 254 | static void init_bg(struct block_group_info *bg, unsigned int i) |
| 255 | { |
| 256 | int header_blocks = 2 + aux_info.inode_table_blocks; |
| 257 | |
| 258 | bg->has_superblock = ext4_bg_has_super_block(i); |
| 259 | |
| 260 | if (bg->has_superblock) |
Colin Cross | 22742ce | 2010-12-22 16:01:52 -0800 | [diff] [blame] | 261 | 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] | 262 | |
| 263 | bg->bitmaps = calloc(info.block_size, 2); |
| 264 | bg->block_bitmap = bg->bitmaps; |
| 265 | bg->inode_bitmap = bg->bitmaps + info.block_size; |
| 266 | |
| 267 | bg->header_blocks = header_blocks; |
| 268 | bg->first_block = aux_info.first_data_block + i * info.blocks_per_group; |
| 269 | |
| 270 | u32 block = bg->first_block; |
| 271 | if (bg->has_superblock) |
Colin Cross | 22742ce | 2010-12-22 16:01:52 -0800 | [diff] [blame] | 272 | block += 1 + aux_info.bg_desc_blocks + info.bg_desc_reserve_blocks; |
Colin Cross | 782879a | 2014-01-23 13:08:16 -0800 | [diff] [blame] | 273 | 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] | 274 | block); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 275 | |
| 276 | bg->data_blocks_used = 0; |
| 277 | bg->free_blocks = info.blocks_per_group; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 278 | bg->free_inodes = info.inodes_per_group; |
| 279 | bg->first_free_inode = 1; |
Mohamad Ayyash | dedf8f9 | 2016-04-14 19:43:31 -0700 | [diff] [blame^] | 280 | bg->flags = EXT4_BG_INODE_UNINIT; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 281 | |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 282 | bg->chunk_count = 0; |
| 283 | bg->max_chunk_count = 1; |
| 284 | bg->chunks = (struct region*) calloc(bg->max_chunk_count, sizeof(struct region)); |
| 285 | |
Mohamad Ayyash | a6866eb | 2016-03-02 21:10:45 -0800 | [diff] [blame] | 286 | if (reserve_blocks(bg, i, 0, bg->header_blocks) < 0) |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 287 | error("failed to reserve %u blocks in block group %u\n", bg->header_blocks, i); |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 288 | // Add empty starting delimiter chunk |
| 289 | reserve_bg_chunk(i, bg->header_blocks, 0); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 290 | |
Ken Sumrall | 17de654 | 2013-08-15 19:06:29 -0700 | [diff] [blame] | 291 | if (bg->first_block + info.blocks_per_group > aux_info.len_blocks) { |
| 292 | u32 overrun = bg->first_block + info.blocks_per_group - aux_info.len_blocks; |
Mohamad Ayyash | a6866eb | 2016-03-02 21:10:45 -0800 | [diff] [blame] | 293 | reserve_blocks(bg, i, info.blocks_per_group - overrun, overrun); |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 294 | // Add empty ending delimiter chunk |
| 295 | reserve_bg_chunk(i, info.blocks_per_group - overrun, 0); |
| 296 | } else { |
| 297 | reserve_bg_chunk(i, info.blocks_per_group - 1, 0); |
Ken Sumrall | 17de654 | 2013-08-15 19:06:29 -0700 | [diff] [blame] | 298 | } |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 299 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 300 | } |
| 301 | |
| 302 | void block_allocator_init() |
| 303 | { |
| 304 | unsigned int i; |
| 305 | |
| 306 | aux_info.bgs = calloc(sizeof(struct block_group_info), aux_info.groups); |
| 307 | if (aux_info.bgs == NULL) |
| 308 | critical_error_errno("calloc"); |
| 309 | |
| 310 | for (i = 0; i < aux_info.groups; i++) |
| 311 | init_bg(&aux_info.bgs[i], i); |
| 312 | } |
| 313 | |
| 314 | void block_allocator_free() |
| 315 | { |
| 316 | unsigned int i; |
| 317 | |
| 318 | for (i = 0; i < aux_info.groups; i++) { |
| 319 | free(aux_info.bgs[i].bitmaps); |
| 320 | free(aux_info.bgs[i].inode_table); |
| 321 | } |
| 322 | free(aux_info.bgs); |
| 323 | } |
| 324 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 325 | /* Allocate a single block and return its block number */ |
| 326 | u32 allocate_block() |
| 327 | { |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 328 | u32 block; |
| 329 | struct block_allocation *blk_alloc = allocate_blocks(1); |
| 330 | if (!blk_alloc) { |
| 331 | return EXT4_ALLOCATE_FAILED; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 332 | } |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 333 | block = blk_alloc->list.first->block; |
| 334 | free_alloc(blk_alloc); |
| 335 | return block; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 336 | } |
| 337 | |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 338 | static struct region *ext4_allocate_best_fit_partial(u32 len) |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 339 | { |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 340 | unsigned int i, j; |
| 341 | unsigned int found_bg = 0, found_prev_chunk = 0, found_block = 0; |
| 342 | u32 found_allocate_len = 0; |
| 343 | bool minimize = false; |
| 344 | struct block_group_info *bgs = aux_info.bgs; |
| 345 | struct region *reg; |
Mohamad Ayyash | 18785a8 | 2016-02-19 21:16:34 +0000 | [diff] [blame] | 346 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 347 | for (i = 0; i < aux_info.groups; i++) { |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 348 | for (j = 1; j < bgs[i].chunk_count; j++) { |
| 349 | u32 hole_start, hole_size; |
| 350 | hole_start = bgs[i].chunks[j-1].block + bgs[i].chunks[j-1].len; |
| 351 | hole_size = bgs[i].chunks[j].block - hole_start; |
| 352 | if (hole_size == len) { |
| 353 | // Perfect fit i.e. right between 2 chunks no need to keep searching |
| 354 | found_bg = i; |
| 355 | found_prev_chunk = j - 1; |
| 356 | found_block = hole_start; |
| 357 | found_allocate_len = hole_size; |
| 358 | goto done; |
| 359 | } else if (hole_size > len && (found_allocate_len == 0 || (found_allocate_len > hole_size))) { |
| 360 | found_bg = i; |
| 361 | found_prev_chunk = j - 1; |
| 362 | found_block = hole_start; |
| 363 | found_allocate_len = hole_size; |
| 364 | minimize = true; |
| 365 | } else if (!minimize) { |
| 366 | if (found_allocate_len < hole_size) { |
| 367 | found_bg = i; |
| 368 | found_prev_chunk = j - 1; |
| 369 | found_block = hole_start; |
| 370 | found_allocate_len = hole_size; |
| 371 | } |
| 372 | } |
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 | |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 376 | if (found_allocate_len == 0) { |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 377 | error("failed to allocate %u blocks, out of space?", len); |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 378 | return NULL; |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 379 | } |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 380 | if (found_allocate_len > len) found_allocate_len = len; |
| 381 | done: |
| 382 | // reclaim allocated space in chunk |
| 383 | bgs[found_bg].chunks[found_prev_chunk].len += found_allocate_len; |
| 384 | if (reserve_blocks(&bgs[found_bg], |
Mohamad Ayyash | a6866eb | 2016-03-02 21:10:45 -0800 | [diff] [blame] | 385 | found_bg, |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 386 | found_block, |
| 387 | found_allocate_len) < 0) { |
| 388 | error("failed to reserve %u blocks in block group %u\n", found_allocate_len, found_bg); |
| 389 | return NULL; |
| 390 | } |
| 391 | bgs[found_bg].data_blocks_used += found_allocate_len; |
| 392 | reg = malloc(sizeof(struct region)); |
| 393 | reg->block = found_block + bgs[found_bg].first_block; |
| 394 | reg->len = found_allocate_len; |
| 395 | reg->next = NULL; |
| 396 | reg->prev = NULL; |
| 397 | reg->bg = found_bg; |
| 398 | return reg; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 399 | } |
| 400 | |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 401 | static struct region *ext4_allocate_best_fit(u32 len) |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 402 | { |
| 403 | struct region *first_reg = NULL; |
| 404 | struct region *prev_reg = NULL; |
| 405 | struct region *reg; |
| 406 | |
| 407 | while (len > 0) { |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 408 | reg = ext4_allocate_best_fit_partial(len); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 409 | if (reg == NULL) |
| 410 | return NULL; |
| 411 | |
| 412 | if (first_reg == NULL) |
| 413 | first_reg = reg; |
| 414 | |
| 415 | if (prev_reg) { |
| 416 | prev_reg->next = reg; |
| 417 | reg->prev = prev_reg; |
| 418 | } |
| 419 | |
| 420 | prev_reg = reg; |
| 421 | len -= reg->len; |
| 422 | } |
| 423 | |
| 424 | return first_reg; |
| 425 | } |
| 426 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 427 | /* Allocate len blocks. The blocks may be spread across multiple block groups, |
| 428 | and are returned in a linked list of the blocks in each block group. The |
| 429 | allocation algorithm is: |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 430 | 1. If the remaining allocation is larger than any available contiguous region, |
| 431 | allocate the largest contiguous region and loop |
| 432 | 2. Otherwise, allocate the smallest contiguous region that it fits in |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 433 | */ |
| 434 | struct block_allocation *allocate_blocks(u32 len) |
| 435 | { |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 436 | struct region *reg = ext4_allocate_best_fit(len); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 437 | |
| 438 | if (reg == NULL) |
| 439 | return NULL; |
| 440 | |
| 441 | struct block_allocation *alloc = create_allocation(); |
| 442 | alloc->list.first = reg; |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 443 | while (reg->next != NULL) |
| 444 | reg = reg->next; |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 445 | alloc->list.last = reg; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 446 | alloc->list.iter = alloc->list.first; |
| 447 | alloc->list.partial_iter = 0; |
| 448 | return alloc; |
| 449 | } |
| 450 | |
| 451 | /* Returns the number of discontiguous regions used by an allocation */ |
| 452 | int block_allocation_num_regions(struct block_allocation *alloc) |
| 453 | { |
| 454 | unsigned int i; |
| 455 | struct region *reg = alloc->list.first; |
| 456 | |
| 457 | for (i = 0; reg != NULL; reg = reg->next) |
| 458 | i++; |
| 459 | |
| 460 | return i; |
| 461 | } |
| 462 | |
| 463 | int block_allocation_len(struct block_allocation *alloc) |
| 464 | { |
| 465 | unsigned int i; |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 466 | struct region *reg = alloc->list.first; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 467 | |
| 468 | for (i = 0; reg != NULL; reg = reg->next) |
| 469 | i += reg->len; |
| 470 | |
| 471 | return i; |
| 472 | } |
| 473 | |
| 474 | /* Returns the block number of the block'th block in an allocation */ |
| 475 | u32 get_block(struct block_allocation *alloc, u32 block) |
| 476 | { |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 477 | struct region *reg = alloc->list.iter; |
| 478 | block += alloc->list.partial_iter; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 479 | |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 480 | for (; reg; reg = reg->next) { |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 481 | if (block < reg->len) |
| 482 | return reg->block + block; |
| 483 | block -= reg->len; |
| 484 | } |
| 485 | return EXT4_ALLOCATE_FAILED; |
| 486 | } |
| 487 | |
| 488 | u32 get_oob_block(struct block_allocation *alloc, u32 block) |
| 489 | { |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 490 | struct region *reg = alloc->oob_list.iter; |
| 491 | block += alloc->oob_list.partial_iter; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 492 | |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 493 | for (; reg; reg = reg->next) { |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 494 | if (block < reg->len) |
| 495 | return reg->block + block; |
| 496 | block -= reg->len; |
| 497 | } |
| 498 | return EXT4_ALLOCATE_FAILED; |
| 499 | } |
| 500 | |
| 501 | /* Gets the starting block and length in blocks of the first region |
| 502 | of an allocation */ |
| 503 | void get_region(struct block_allocation *alloc, u32 *block, u32 *len) |
| 504 | { |
| 505 | *block = alloc->list.iter->block; |
| 506 | *len = alloc->list.iter->len - alloc->list.partial_iter; |
| 507 | } |
| 508 | |
| 509 | /* Move to the next region in an allocation */ |
| 510 | void get_next_region(struct block_allocation *alloc) |
| 511 | { |
| 512 | alloc->list.iter = alloc->list.iter->next; |
| 513 | alloc->list.partial_iter = 0; |
| 514 | } |
| 515 | |
| 516 | /* Returns the number of free blocks in a block group */ |
| 517 | u32 get_free_blocks(u32 bg) |
| 518 | { |
| 519 | return aux_info.bgs[bg].free_blocks; |
| 520 | } |
| 521 | |
| 522 | int last_region(struct block_allocation *alloc) |
| 523 | { |
| 524 | return (alloc->list.iter == NULL); |
| 525 | } |
| 526 | |
| 527 | void rewind_alloc(struct block_allocation *alloc) |
| 528 | { |
| 529 | alloc->list.iter = alloc->list.first; |
| 530 | alloc->list.partial_iter = 0; |
| 531 | } |
| 532 | |
| 533 | static struct region *do_split_allocation(struct block_allocation *alloc, u32 len) |
| 534 | { |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 535 | struct region *reg = alloc->list.iter; |
| 536 | struct region *new; |
| 537 | struct region *tmp; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 538 | |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 539 | while (reg && len >= reg->len) { |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 540 | len -= reg->len; |
| 541 | reg = reg->next; |
| 542 | } |
| 543 | |
| 544 | if (reg == NULL && len > 0) |
| 545 | return NULL; |
| 546 | |
| 547 | if (len > 0) { |
| 548 | new = malloc(sizeof(struct region)); |
| 549 | |
| 550 | new->bg = reg->bg; |
| 551 | new->block = reg->block + len; |
| 552 | new->len = reg->len - len; |
| 553 | new->next = reg->next; |
| 554 | new->prev = reg; |
| 555 | |
| 556 | reg->next = new; |
| 557 | reg->len = len; |
| 558 | |
| 559 | tmp = alloc->list.iter; |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 560 | alloc->list.iter = new; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 561 | return tmp; |
| 562 | } else { |
| 563 | return reg; |
| 564 | } |
| 565 | } |
| 566 | |
| 567 | /* Splits an allocation into two allocations. The returned allocation will |
| 568 | point to the first half, and the original allocation ptr will point to the |
| 569 | second half. */ |
| 570 | static struct region *split_allocation(struct block_allocation *alloc, u32 len) |
| 571 | { |
| 572 | /* First make sure there is a split at the current ptr */ |
| 573 | do_split_allocation(alloc, alloc->list.partial_iter); |
| 574 | |
| 575 | /* Then split off len blocks */ |
| 576 | struct region *middle = do_split_allocation(alloc, len); |
| 577 | alloc->list.partial_iter = 0; |
| 578 | return middle; |
| 579 | } |
| 580 | |
| 581 | /* Reserve the next blocks for oob data (indirect or extent blocks) */ |
| 582 | int reserve_oob_blocks(struct block_allocation *alloc, int blocks) |
| 583 | { |
| 584 | struct region *oob = split_allocation(alloc, blocks); |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 585 | struct region *next; |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 586 | |
| 587 | if (oob == NULL) |
| 588 | return -1; |
| 589 | |
| 590 | while (oob && oob != alloc->list.iter) { |
| 591 | next = oob->next; |
| 592 | region_list_remove(&alloc->list, oob); |
| 593 | region_list_append(&alloc->oob_list, oob); |
| 594 | oob = next; |
| 595 | } |
| 596 | |
| 597 | return 0; |
| 598 | } |
| 599 | |
| 600 | static int advance_list_ptr(struct region_list *list, int blocks) |
| 601 | { |
| 602 | struct region *reg = list->iter; |
| 603 | |
| 604 | while (reg != NULL && blocks > 0) { |
| 605 | if (reg->len > list->partial_iter + blocks) { |
| 606 | list->partial_iter += blocks; |
| 607 | return 0; |
| 608 | } |
| 609 | |
| 610 | blocks -= (reg->len - list->partial_iter); |
| 611 | list->partial_iter = 0; |
| 612 | reg = reg->next; |
| 613 | } |
| 614 | |
| 615 | if (blocks > 0) |
| 616 | return -1; |
| 617 | |
| 618 | return 0; |
| 619 | } |
| 620 | |
| 621 | /* Move the allocation pointer forward */ |
| 622 | int advance_blocks(struct block_allocation *alloc, int blocks) |
| 623 | { |
| 624 | return advance_list_ptr(&alloc->list, blocks); |
| 625 | } |
| 626 | |
| 627 | int advance_oob_blocks(struct block_allocation *alloc, int blocks) |
| 628 | { |
| 629 | return advance_list_ptr(&alloc->oob_list, blocks); |
| 630 | } |
| 631 | |
| 632 | int append_oob_allocation(struct block_allocation *alloc, u32 len) |
| 633 | { |
Colin Cross | eb3915a | 2014-01-21 00:04:04 -0800 | [diff] [blame] | 634 | struct region *reg = ext4_allocate_best_fit(len); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 635 | |
| 636 | if (reg == NULL) { |
| 637 | error("failed to allocate %d blocks", len); |
| 638 | return -1; |
| 639 | } |
| 640 | |
| 641 | for (; reg; reg = reg->next) |
| 642 | region_list_append(&alloc->oob_list, reg); |
| 643 | |
| 644 | return 0; |
| 645 | } |
| 646 | |
| 647 | /* Returns an ext4_inode structure for an inode number */ |
| 648 | struct ext4_inode *get_inode(u32 inode) |
| 649 | { |
| 650 | inode -= 1; |
| 651 | int bg = inode / info.inodes_per_group; |
| 652 | inode %= info.inodes_per_group; |
| 653 | |
| 654 | allocate_bg_inode_table(&aux_info.bgs[bg]); |
Colin Cross | 8aef66d | 2010-06-20 23:22:12 -0700 | [diff] [blame] | 655 | return (struct ext4_inode *)(aux_info.bgs[bg].inode_table + inode * |
| 656 | info.inode_size); |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 657 | } |
| 658 | |
Nick Kralevich | 4df62f3 | 2013-02-07 14:21:34 -0800 | [diff] [blame] | 659 | struct ext4_xattr_header *get_xattr_block_for_inode(struct ext4_inode *inode) |
| 660 | { |
| 661 | struct ext4_xattr_header *block = xattr_list_find(inode); |
| 662 | if (block != NULL) |
| 663 | return block; |
| 664 | |
| 665 | u32 block_num = allocate_block(); |
| 666 | block = calloc(info.block_size, 1); |
| 667 | if (block == NULL) { |
| 668 | error("get_xattr: failed to allocate %d", info.block_size); |
| 669 | return NULL; |
| 670 | } |
| 671 | |
| 672 | block->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
| 673 | block->h_refcount = cpu_to_le32(1); |
| 674 | block->h_blocks = cpu_to_le32(1); |
| 675 | inode->i_blocks_lo = cpu_to_le32(le32_to_cpu(inode->i_blocks_lo) + (info.block_size / 512)); |
| 676 | inode->i_file_acl_lo = cpu_to_le32(block_num); |
| 677 | |
Colin Cross | 782879a | 2014-01-23 13:08:16 -0800 | [diff] [blame] | 678 | 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] | 679 | if (result != 0) { |
| 680 | error("get_xattr: sparse_file_add_data failure %d", result); |
| 681 | free(block); |
| 682 | return NULL; |
| 683 | } |
| 684 | xattr_list_insert(inode, block); |
| 685 | return block; |
| 686 | } |
| 687 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 688 | /* Mark the first len inodes in a block group as used */ |
| 689 | u32 reserve_inodes(int bg, u32 num) |
| 690 | { |
| 691 | unsigned int i; |
| 692 | u32 inode; |
| 693 | |
| 694 | if (get_free_inodes(bg) < num) |
| 695 | return EXT4_ALLOCATE_FAILED; |
| 696 | |
| 697 | for (i = 0; i < num; i++) { |
| 698 | inode = aux_info.bgs[bg].first_free_inode + i - 1; |
| 699 | aux_info.bgs[bg].inode_bitmap[inode / 8] |= 1 << (inode % 8); |
| 700 | } |
| 701 | |
| 702 | inode = aux_info.bgs[bg].first_free_inode; |
| 703 | |
| 704 | aux_info.bgs[bg].first_free_inode += num; |
| 705 | aux_info.bgs[bg].free_inodes -= num; |
| 706 | |
| 707 | return inode; |
| 708 | } |
| 709 | |
| 710 | /* Returns the first free inode number |
| 711 | TODO: Inodes should be allocated in the block group of the data? */ |
| 712 | u32 allocate_inode() |
| 713 | { |
| 714 | unsigned int bg; |
| 715 | u32 inode; |
| 716 | |
| 717 | for (bg = 0; bg < aux_info.groups; bg++) { |
| 718 | inode = reserve_inodes(bg, 1); |
| 719 | if (inode != EXT4_ALLOCATE_FAILED) |
| 720 | return bg * info.inodes_per_group + inode; |
| 721 | } |
| 722 | |
| 723 | return EXT4_ALLOCATE_FAILED; |
| 724 | } |
| 725 | |
| 726 | /* Returns the number of free inodes in a block group */ |
| 727 | u32 get_free_inodes(u32 bg) |
| 728 | { |
| 729 | return aux_info.bgs[bg].free_inodes; |
| 730 | } |
| 731 | |
| 732 | /* Increments the directory count of the block group that contains inode */ |
| 733 | void add_directory(u32 inode) |
| 734 | { |
| 735 | int bg = (inode - 1) / info.inodes_per_group; |
| 736 | aux_info.bgs[bg].used_dirs += 1; |
| 737 | } |
| 738 | |
| 739 | /* Returns the number of inodes in a block group that are directories */ |
| 740 | u16 get_directories(int bg) |
| 741 | { |
| 742 | return aux_info.bgs[bg].used_dirs; |
| 743 | } |
| 744 | |
Colin Cross | 56497f2 | 2013-02-04 00:44:55 -0800 | [diff] [blame] | 745 | /* Returns the flags for a block group */ |
| 746 | u16 get_bg_flags(int bg) |
| 747 | { |
| 748 | return aux_info.bgs[bg].flags; |
| 749 | } |
| 750 | |
Colin Cross | ec0a2e8 | 2010-06-11 14:21:37 -0700 | [diff] [blame] | 751 | /* Frees the memory used by a linked list of allocation regions */ |
| 752 | void free_alloc(struct block_allocation *alloc) |
| 753 | { |
| 754 | struct region *reg; |
| 755 | |
| 756 | reg = alloc->list.first; |
| 757 | while (reg) { |
| 758 | struct region *next = reg->next; |
| 759 | free(reg); |
| 760 | reg = next; |
| 761 | } |
| 762 | |
| 763 | reg = alloc->oob_list.first; |
| 764 | while (reg) { |
| 765 | struct region *next = reg->next; |
| 766 | free(reg); |
| 767 | reg = next; |
| 768 | } |
| 769 | |
| 770 | free(alloc); |
| 771 | } |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 772 | |
| 773 | void reserve_bg_chunk(int bg, u32 start_block, u32 size) { |
| 774 | struct block_group_info *bgs = aux_info.bgs; |
| 775 | int chunk_count; |
| 776 | if (bgs[bg].chunk_count == bgs[bg].max_chunk_count) { |
| 777 | bgs[bg].max_chunk_count *= 2; |
| 778 | bgs[bg].chunks = realloc(bgs[bg].chunks, bgs[bg].max_chunk_count * sizeof(struct region)); |
| 779 | if (!bgs[bg].chunks) |
| 780 | critical_error("realloc failed"); |
| 781 | } |
| 782 | chunk_count = bgs[bg].chunk_count; |
| 783 | bgs[bg].chunks[chunk_count].block = start_block; |
| 784 | bgs[bg].chunks[chunk_count].len = size; |
| 785 | bgs[bg].chunks[chunk_count].bg = bg; |
| 786 | bgs[bg].chunk_count++; |
| 787 | } |
| 788 | |
| 789 | int reserve_blocks_for_allocation(struct block_allocation *alloc) { |
| 790 | struct region *reg; |
| 791 | struct block_group_info *bgs = aux_info.bgs; |
| 792 | |
| 793 | if (!alloc) return 0; |
| 794 | reg = alloc->list.first; |
| 795 | while (reg != NULL) { |
Mohamad Ayyash | a6866eb | 2016-03-02 21:10:45 -0800 | [diff] [blame] | 796 | if (reserve_blocks(&bgs[reg->bg], reg->bg, reg->block - bgs[reg->bg].first_block, reg->len) < 0) { |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 797 | return -1; |
Mohamad Ayyash | a6866eb | 2016-03-02 21:10:45 -0800 | [diff] [blame] | 798 | } |
Mohamad Ayyash | 9579198 | 2016-02-20 03:46:00 +0000 | [diff] [blame] | 799 | reg = reg->next; |
| 800 | } |
| 801 | return 0; |
| 802 | } |
| 803 | |