make_ext4fs.c revision 2ae7663e1e064000356ee9e49ebd08bdddc545f9
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 * 8 * http://www.apache.org/licenses/LICENSE-2.0 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 17#include "make_ext4fs.h" 18#include "output_file.h" 19#include "ext4_utils.h" 20#include "allocate.h" 21#include "contents.h" 22#include "uuid.h" 23#include "backed_block.h" 24 25#include <dirent.h> 26#include <libgen.h> 27#include <stdio.h> 28#include <stdlib.h> 29#include <string.h> 30#include <unistd.h> 31#include <sys/stat.h> 32#include <sys/types.h> 33 34#ifdef ANDROID 35#include <private/android_filesystem_config.h> 36#endif 37 38/* TODO: Not implemented: 39 Allocating blocks in the same block group as the file inode 40 Hash or binary tree directories 41 Special files: sockets, devices, fifos 42 */ 43 44static int filter_dot(const struct dirent *d) 45{ 46 return (strcmp(d->d_name, "..") && strcmp(d->d_name, ".")); 47} 48 49static u32 build_default_directory_structure() 50{ 51 u32 inode; 52 u32 root_inode; 53 struct dentry dentries = { 54 .filename = "lost+found", 55 .file_type = EXT4_FT_DIR, 56 .mode = S_IRWXU, 57 .uid = 0, 58 .gid = 0, 59 .mtime = 0, 60 }; 61 root_inode = make_directory(0, 1, &dentries, 1); 62 inode = make_directory(root_inode, 0, NULL, 0); 63 *dentries.inode = inode; 64 inode_set_permissions(inode, dentries.mode, 65 dentries.uid, dentries.gid, dentries.mtime); 66 67 return root_inode; 68} 69 70/* Read a local directory and create the same tree in the generated filesystem. 71 Calls itself recursively with each directory in the given directory */ 72static u32 build_directory_structure(const char *full_path, const char *dir_path, 73 u32 dir_inode, int android) 74{ 75 int entries = 0; 76 struct dentry *dentries; 77 struct dirent **namelist; 78 struct stat stat; 79 int ret; 80 int i; 81 u32 inode; 82 u32 entry_inode; 83 u32 dirs = 0; 84 85 entries = scandir(full_path, &namelist, filter_dot, (void*)alphasort); 86 if (entries < 0) { 87 error_errno("scandir"); 88 return EXT4_ALLOCATE_FAILED; 89 } 90 91 dentries = calloc(entries, sizeof(struct dentry)); 92 if (dentries == NULL) 93 critical_error_errno("malloc"); 94 95 for (i = 0; i < entries; i++) { 96 dentries[i].filename = strdup(namelist[i]->d_name); 97 if (dentries[i].filename == NULL) 98 critical_error_errno("strdup"); 99 100 asprintf(&dentries[i].path, "%s/%s", dir_path, namelist[i]->d_name); 101 asprintf(&dentries[i].full_path, "%s/%s", full_path, namelist[i]->d_name); 102 103 free(namelist[i]); 104 105 ret = lstat(dentries[i].full_path, &stat); 106 if (ret < 0) { 107 error_errno("lstat"); 108 i--; 109 entries--; 110 continue; 111 } 112 113 dentries[i].size = stat.st_size; 114 dentries[i].mode = stat.st_mode & (S_ISUID|S_ISGID|S_ISVTX|S_IRWXU|S_IRWXG|S_IRWXO); 115 dentries[i].mtime = stat.st_mtime; 116 if (android) { 117#ifdef ANDROID 118 unsigned int mode = 0; 119 unsigned int uid = 0; 120 unsigned int gid = 0; 121 int dir = S_ISDIR(stat.st_mode); 122 fs_config(dentries[i].path, dir, &uid, &gid, &mode); 123 dentries[i].mode = mode; 124 dentries[i].uid = uid; 125 dentries[i].gid = gid; 126#else 127 error("can't set android permissions - built without android support"); 128#endif 129 } 130 131 if (S_ISREG(stat.st_mode)) { 132 dentries[i].file_type = EXT4_FT_REG_FILE; 133 } else if (S_ISDIR(stat.st_mode)) { 134 dentries[i].file_type = EXT4_FT_DIR; 135 dirs++; 136 } else if (S_ISCHR(stat.st_mode)) { 137 dentries[i].file_type = EXT4_FT_CHRDEV; 138 } else if (S_ISBLK(stat.st_mode)) { 139 dentries[i].file_type = EXT4_FT_BLKDEV; 140 } else if (S_ISFIFO(stat.st_mode)) { 141 dentries[i].file_type = EXT4_FT_FIFO; 142 } else if (S_ISSOCK(stat.st_mode)) { 143 dentries[i].file_type = EXT4_FT_SOCK; 144 } else if (S_ISLNK(stat.st_mode)) { 145 dentries[i].file_type = EXT4_FT_SYMLINK; 146 dentries[i].link = calloc(info.block_size, 1); 147 readlink(dentries[i].full_path, dentries[i].link, info.block_size - 1); 148 } else { 149 error("unknown file type on %s", dentries[i].path); 150 i--; 151 entries--; 152 } 153 } 154 free(namelist); 155 156 inode = make_directory(dir_inode, entries, dentries, dirs); 157 158 for (i = 0; i < entries; i++) { 159 if (dentries[i].file_type == EXT4_FT_REG_FILE) { 160 entry_inode = make_file(dentries[i].full_path, dentries[i].size); 161 } else if (dentries[i].file_type == EXT4_FT_DIR) { 162 entry_inode = build_directory_structure(dentries[i].full_path, 163 dentries[i].path, inode, android); 164 } else if (dentries[i].file_type == EXT4_FT_SYMLINK) { 165 entry_inode = make_link(dentries[i].full_path, dentries[i].link); 166 } else { 167 error("unknown file type on %s", dentries[i].path); 168 entry_inode = 0; 169 } 170 *dentries[i].inode = entry_inode; 171 172 ret = inode_set_permissions(entry_inode, dentries[i].mode, 173 dentries[i].uid, dentries[i].gid, 174 dentries[i].mtime); 175 if (ret) 176 error("failed to set permissions on %s\n", dentries[i].path); 177 178 free(dentries[i].path); 179 free(dentries[i].full_path); 180 free(dentries[i].link); 181 free((void *)dentries[i].filename); 182 } 183 184 free(dentries); 185 return inode; 186} 187 188static u32 compute_block_size() 189{ 190 return 4096; 191} 192 193static u32 compute_journal_blocks() 194{ 195 u32 journal_blocks = DIV_ROUND_UP(info.len, info.block_size) / 64; 196 if (journal_blocks < 1024) 197 journal_blocks = 1024; 198 if (journal_blocks > 32768) 199 journal_blocks = 32768; 200 return journal_blocks; 201} 202 203static u32 compute_blocks_per_group() 204{ 205 return info.block_size * 8; 206} 207 208static u32 compute_inodes() 209{ 210 return DIV_ROUND_UP(info.len, info.block_size) / 4; 211} 212 213static u32 compute_inodes_per_group() 214{ 215 u32 blocks = DIV_ROUND_UP(info.len, info.block_size); 216 u32 block_groups = DIV_ROUND_UP(blocks, info.blocks_per_group); 217 return DIV_ROUND_UP(info.inodes, block_groups); 218} 219 220static u32 compute_bg_desc_reserve_blocks() 221{ 222 u32 blocks = DIV_ROUND_UP(info.len, info.block_size); 223 u32 block_groups = DIV_ROUND_UP(blocks, info.blocks_per_group); 224 u32 bg_desc_blocks = DIV_ROUND_UP(block_groups * sizeof(struct ext2_group_desc), 225 info.block_size); 226 227 u32 bg_desc_reserve_blocks = 228 DIV_ROUND_UP(block_groups * 1024 * sizeof(struct ext2_group_desc), 229 info.block_size) - bg_desc_blocks; 230 231 if (bg_desc_reserve_blocks > info.block_size / sizeof(u32)) 232 bg_desc_reserve_blocks = info.block_size / sizeof(u32); 233 234 return bg_desc_reserve_blocks; 235} 236 237void reset_ext4fs_info() { 238 // Reset all the global data structures used by make_ext4fs so it 239 // can be called again. 240 memset(&info, 0, sizeof(info)); 241 memset(&aux_info, 0, sizeof(aux_info)); 242 free_data_blocks(); 243} 244 245int make_ext4fs(const char *filename, s64 len) 246{ 247 reset_ext4fs_info(); 248 info.len = len; 249 return make_ext4fs_internal(filename, NULL, NULL, 0, 0, 0, 0, 1); 250} 251 252int make_ext4fs_internal(const char *filename, const char *directory, 253 char *mountpoint, int android, int gzip, int sparse, 254 int crc, int wipe) 255{ 256 u32 root_inode_num; 257 u16 root_mode; 258 259 if (setjmp(setjmp_env)) 260 return EXIT_FAILURE; /* Handle a call to longjmp() */ 261 262 if (info.len <= 0) 263 info.len = get_file_size(filename); 264 265 if (info.len <= 0) { 266 fprintf(stderr, "Need size of filesystem\n"); 267 return EXIT_FAILURE; 268 } 269 270 if (info.block_size <= 0) 271 info.block_size = compute_block_size(); 272 273 if (info.journal_blocks == 0) 274 info.journal_blocks = compute_journal_blocks(); 275 276 if (info.no_journal == 0) 277 info.feat_compat = EXT4_FEATURE_COMPAT_HAS_JOURNAL; 278 else 279 info.journal_blocks = 0; 280 281 if (info.blocks_per_group <= 0) 282 info.blocks_per_group = compute_blocks_per_group(); 283 284 if (info.inodes <= 0) 285 info.inodes = compute_inodes(); 286 287 if (info.inode_size <= 0) 288 info.inode_size = 256; 289 290 if (info.label == NULL) 291 info.label = ""; 292 293 info.inodes_per_group = compute_inodes_per_group(); 294 295 info.feat_compat |= 296 EXT4_FEATURE_COMPAT_RESIZE_INODE; 297 298 info.feat_ro_compat |= 299 EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER | 300 EXT4_FEATURE_RO_COMPAT_LARGE_FILE; 301 302 info.feat_incompat |= 303 EXT4_FEATURE_INCOMPAT_EXTENTS | 304 EXT4_FEATURE_INCOMPAT_FILETYPE; 305 306 307 info.bg_desc_reserve_blocks = compute_bg_desc_reserve_blocks(); 308 309 printf("Creating filesystem with parameters:\n"); 310 printf(" Size: %llu\n", info.len); 311 printf(" Block size: %d\n", info.block_size); 312 printf(" Blocks per group: %d\n", info.blocks_per_group); 313 printf(" Inodes per group: %d\n", info.inodes_per_group); 314 printf(" Inode size: %d\n", info.inode_size); 315 printf(" Journal blocks: %d\n", info.journal_blocks); 316 printf(" Label: %s\n", info.label); 317 318 ext4_create_fs_aux_info(); 319 320 printf(" Blocks: %llu\n", aux_info.len_blocks); 321 printf(" Block groups: %d\n", aux_info.groups); 322 printf(" Reserved block group size: %d\n", info.bg_desc_reserve_blocks); 323 324 block_allocator_init(); 325 326 ext4_fill_in_sb(); 327 328 if (reserve_inodes(0, 10) == EXT4_ALLOCATE_FAILED) 329 error("failed to reserve first 10 inodes"); 330 331 if (info.feat_compat & EXT4_FEATURE_COMPAT_HAS_JOURNAL) 332 ext4_create_journal_inode(); 333 334 if (info.feat_compat & EXT4_FEATURE_COMPAT_RESIZE_INODE) 335 ext4_create_resize_inode(); 336 337 if (directory) 338 root_inode_num = build_directory_structure(directory, mountpoint, 0, android); 339 else 340 root_inode_num = build_default_directory_structure(); 341 342 root_mode = S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH; 343 inode_set_permissions(root_inode_num, root_mode, 0, 0, 0); 344 345 ext4_update_free(); 346 347 ext4_queue_sb(); 348 349 printf("Created filesystem with %d/%d inodes and %d/%d blocks\n", 350 aux_info.sb->s_inodes_count - aux_info.sb->s_free_inodes_count, 351 aux_info.sb->s_inodes_count, 352 aux_info.sb->s_blocks_count_lo - aux_info.sb->s_free_blocks_count_lo, 353 aux_info.sb->s_blocks_count_lo); 354 355 write_ext4_image(filename, gzip, sparse, crc, wipe); 356 357 return 0; 358} 359