make_ext4fs.c revision 93eb1dc9e68d2e9dea94f56d8bce478c1a52b354
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 <fcntl.h> 27#include <libgen.h> 28#include <stdio.h> 29#include <stdlib.h> 30#include <string.h> 31#include <unistd.h> 32#include <sys/stat.h> 33#include <sys/types.h> 34 35#ifdef ANDROID 36#include <private/android_filesystem_config.h> 37#endif 38 39/* TODO: Not implemented: 40 Allocating blocks in the same block group as the file inode 41 Hash or binary tree directories 42 Special files: sockets, devices, fifos 43 */ 44 45static int filter_dot(const struct dirent *d) 46{ 47 return (strcmp(d->d_name, "..") && strcmp(d->d_name, ".")); 48} 49 50static u32 build_default_directory_structure() 51{ 52 u32 inode; 53 u32 root_inode; 54 struct dentry dentries = { 55 .filename = "lost+found", 56 .file_type = EXT4_FT_DIR, 57 .mode = S_IRWXU, 58 .uid = 0, 59 .gid = 0, 60 .mtime = 0, 61 }; 62 root_inode = make_directory(0, 1, &dentries, 1); 63 inode = make_directory(root_inode, 0, NULL, 0); 64 *dentries.inode = inode; 65 inode_set_permissions(inode, dentries.mode, 66 dentries.uid, dentries.gid, dentries.mtime); 67 68 return root_inode; 69} 70 71/* Read a local directory and create the same tree in the generated filesystem. 72 Calls itself recursively with each directory in the given directory */ 73static u32 build_directory_structure(const char *full_path, const char *dir_path, 74 u32 dir_inode, int android) 75{ 76 int entries = 0; 77 struct dentry *dentries; 78 struct dirent **namelist; 79 struct stat stat; 80 int ret; 81 int i; 82 u32 inode; 83 u32 entry_inode; 84 u32 dirs = 0; 85 86 entries = scandir(full_path, &namelist, filter_dot, (void*)alphasort); 87 if (entries < 0) { 88 error_errno("scandir"); 89 return EXT4_ALLOCATE_FAILED; 90 } 91 92 dentries = calloc(entries, sizeof(struct dentry)); 93 if (dentries == NULL) 94 critical_error_errno("malloc"); 95 96 for (i = 0; i < entries; i++) { 97 dentries[i].filename = strdup(namelist[i]->d_name); 98 if (dentries[i].filename == NULL) 99 critical_error_errno("strdup"); 100 101 asprintf(&dentries[i].path, "%s/%s", dir_path, namelist[i]->d_name); 102 asprintf(&dentries[i].full_path, "%s/%s", full_path, namelist[i]->d_name); 103 104 free(namelist[i]); 105 106 ret = lstat(dentries[i].full_path, &stat); 107 if (ret < 0) { 108 error_errno("lstat"); 109 i--; 110 entries--; 111 continue; 112 } 113 114 dentries[i].size = stat.st_size; 115 dentries[i].mode = stat.st_mode & (S_ISUID|S_ISGID|S_ISVTX|S_IRWXU|S_IRWXG|S_IRWXO); 116 dentries[i].mtime = stat.st_mtime; 117 if (android) { 118#ifdef ANDROID 119 unsigned int mode = 0; 120 unsigned int uid = 0; 121 unsigned int gid = 0; 122 int dir = S_ISDIR(stat.st_mode); 123 fs_config(dentries[i].path, dir, &uid, &gid, &mode); 124 dentries[i].mode = mode; 125 dentries[i].uid = uid; 126 dentries[i].gid = gid; 127#else 128 error("can't set android permissions - built without android support"); 129#endif 130 } 131 132 if (S_ISREG(stat.st_mode)) { 133 dentries[i].file_type = EXT4_FT_REG_FILE; 134 } else if (S_ISDIR(stat.st_mode)) { 135 dentries[i].file_type = EXT4_FT_DIR; 136 dirs++; 137 } else if (S_ISCHR(stat.st_mode)) { 138 dentries[i].file_type = EXT4_FT_CHRDEV; 139 } else if (S_ISBLK(stat.st_mode)) { 140 dentries[i].file_type = EXT4_FT_BLKDEV; 141 } else if (S_ISFIFO(stat.st_mode)) { 142 dentries[i].file_type = EXT4_FT_FIFO; 143 } else if (S_ISSOCK(stat.st_mode)) { 144 dentries[i].file_type = EXT4_FT_SOCK; 145 } else if (S_ISLNK(stat.st_mode)) { 146 dentries[i].file_type = EXT4_FT_SYMLINK; 147 dentries[i].link = calloc(info.block_size, 1); 148 readlink(dentries[i].full_path, dentries[i].link, info.block_size - 1); 149 } else { 150 error("unknown file type on %s", dentries[i].path); 151 i--; 152 entries--; 153 } 154 } 155 free(namelist); 156 157 inode = make_directory(dir_inode, entries, dentries, dirs); 158 159 for (i = 0; i < entries; i++) { 160 if (dentries[i].file_type == EXT4_FT_REG_FILE) { 161 entry_inode = make_file(dentries[i].full_path, dentries[i].size); 162 } else if (dentries[i].file_type == EXT4_FT_DIR) { 163 entry_inode = build_directory_structure(dentries[i].full_path, 164 dentries[i].path, inode, android); 165 } else if (dentries[i].file_type == EXT4_FT_SYMLINK) { 166 entry_inode = make_link(dentries[i].full_path, dentries[i].link); 167 } else { 168 error("unknown file type on %s", dentries[i].path); 169 entry_inode = 0; 170 } 171 *dentries[i].inode = entry_inode; 172 173 ret = inode_set_permissions(entry_inode, dentries[i].mode, 174 dentries[i].uid, dentries[i].gid, 175 dentries[i].mtime); 176 if (ret) 177 error("failed to set permissions on %s\n", dentries[i].path); 178 179 free(dentries[i].path); 180 free(dentries[i].full_path); 181 free(dentries[i].link); 182 free((void *)dentries[i].filename); 183 } 184 185 free(dentries); 186 return inode; 187} 188 189static u32 compute_block_size() 190{ 191 return 4096; 192} 193 194static u32 compute_journal_blocks() 195{ 196 u32 journal_blocks = DIV_ROUND_UP(info.len, info.block_size) / 64; 197 if (journal_blocks < 1024) 198 journal_blocks = 1024; 199 if (journal_blocks > 32768) 200 journal_blocks = 32768; 201 return journal_blocks; 202} 203 204static u32 compute_blocks_per_group() 205{ 206 return info.block_size * 8; 207} 208 209static u32 compute_inodes() 210{ 211 return DIV_ROUND_UP(info.len, info.block_size) / 4; 212} 213 214static u32 compute_inodes_per_group() 215{ 216 u32 blocks = DIV_ROUND_UP(info.len, info.block_size); 217 u32 block_groups = DIV_ROUND_UP(blocks, info.blocks_per_group); 218 u32 inodes = DIV_ROUND_UP(info.inodes, block_groups); 219 inodes = ALIGN(inodes, (info.block_size / info.inode_size)); 220 221 /* After properly rounding up the number of inodes/group, 222 * make sure to update the total inodes field in the info struct. 223 */ 224 info.inodes = inodes * block_groups; 225 226 return inodes; 227} 228 229static u32 compute_bg_desc_reserve_blocks() 230{ 231 u32 blocks = DIV_ROUND_UP(info.len, info.block_size); 232 u32 block_groups = DIV_ROUND_UP(blocks, info.blocks_per_group); 233 u32 bg_desc_blocks = DIV_ROUND_UP(block_groups * sizeof(struct ext2_group_desc), 234 info.block_size); 235 236 u32 bg_desc_reserve_blocks = 237 DIV_ROUND_UP(block_groups * 1024 * sizeof(struct ext2_group_desc), 238 info.block_size) - bg_desc_blocks; 239 240 if (bg_desc_reserve_blocks > info.block_size / sizeof(u32)) 241 bg_desc_reserve_blocks = info.block_size / sizeof(u32); 242 243 return bg_desc_reserve_blocks; 244} 245 246void reset_ext4fs_info() { 247 // Reset all the global data structures used by make_ext4fs so it 248 // can be called again. 249 memset(&info, 0, sizeof(info)); 250 memset(&aux_info, 0, sizeof(aux_info)); 251 free_data_blocks(); 252} 253 254int make_ext4fs(const char *filename, s64 len) 255{ 256 int fd; 257 int status; 258 259 reset_ext4fs_info(); 260 info.len = len; 261 262 fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0644); 263 if (fd < 0) { 264 error_errno("open"); 265 return EXIT_FAILURE; 266 } 267 268 status = make_ext4fs_internal(fd, NULL, NULL, 0, 0, 0, 0, 1, 0); 269 close(fd); 270 271 return status; 272} 273 274int make_ext4fs_internal(int fd, const char *directory, 275 char *mountpoint, int android, int gzip, int sparse, 276 int crc, int wipe, int init_itabs) 277{ 278 u32 root_inode_num; 279 u16 root_mode; 280 281 if (setjmp(setjmp_env)) 282 return EXIT_FAILURE; /* Handle a call to longjmp() */ 283 284 if (info.len <= 0) 285 info.len = get_file_size(fd); 286 287 if (info.len <= 0) { 288 fprintf(stderr, "Need size of filesystem\n"); 289 return EXIT_FAILURE; 290 } 291 292 if (info.block_size <= 0) 293 info.block_size = compute_block_size(); 294 295 /* Round down the filesystem length to be a multiple of the block size */ 296 info.len &= ~((u64)info.block_size - 1); 297 298 if (info.journal_blocks == 0) 299 info.journal_blocks = compute_journal_blocks(); 300 301 if (info.no_journal == 0) 302 info.feat_compat = EXT4_FEATURE_COMPAT_HAS_JOURNAL; 303 else 304 info.journal_blocks = 0; 305 306 if (info.blocks_per_group <= 0) 307 info.blocks_per_group = compute_blocks_per_group(); 308 309 if (info.inodes <= 0) 310 info.inodes = compute_inodes(); 311 312 if (info.inode_size <= 0) 313 info.inode_size = 256; 314 315 if (info.label == NULL) 316 info.label = ""; 317 318 info.inodes_per_group = compute_inodes_per_group(); 319 320 info.feat_compat |= 321 EXT4_FEATURE_COMPAT_RESIZE_INODE; 322 323 info.feat_ro_compat |= 324 EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER | 325 EXT4_FEATURE_RO_COMPAT_LARGE_FILE; 326 327 info.feat_incompat |= 328 EXT4_FEATURE_INCOMPAT_EXTENTS | 329 EXT4_FEATURE_INCOMPAT_FILETYPE; 330 331 332 info.bg_desc_reserve_blocks = compute_bg_desc_reserve_blocks(); 333 334 printf("Creating filesystem with parameters:\n"); 335 printf(" Size: %llu\n", info.len); 336 printf(" Block size: %d\n", info.block_size); 337 printf(" Blocks per group: %d\n", info.blocks_per_group); 338 printf(" Inodes per group: %d\n", info.inodes_per_group); 339 printf(" Inode size: %d\n", info.inode_size); 340 printf(" Journal blocks: %d\n", info.journal_blocks); 341 printf(" Label: %s\n", info.label); 342 343 ext4_create_fs_aux_info(); 344 345 printf(" Blocks: %llu\n", aux_info.len_blocks); 346 printf(" Block groups: %d\n", aux_info.groups); 347 printf(" Reserved block group size: %d\n", info.bg_desc_reserve_blocks); 348 349 block_allocator_init(); 350 351 ext4_fill_in_sb(); 352 353 if (reserve_inodes(0, 10) == EXT4_ALLOCATE_FAILED) 354 error("failed to reserve first 10 inodes"); 355 356 if (info.feat_compat & EXT4_FEATURE_COMPAT_HAS_JOURNAL) 357 ext4_create_journal_inode(); 358 359 if (info.feat_compat & EXT4_FEATURE_COMPAT_RESIZE_INODE) 360 ext4_create_resize_inode(); 361 362 if (directory) 363 root_inode_num = build_directory_structure(directory, mountpoint, 0, android); 364 else 365 root_inode_num = build_default_directory_structure(); 366 367 root_mode = S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH; 368 inode_set_permissions(root_inode_num, root_mode, 0, 0, 0); 369 370 ext4_update_free(); 371 372 if (init_itabs) 373 init_unused_inode_tables(); 374 375 ext4_queue_sb(); 376 377 printf("Created filesystem with %d/%d inodes and %d/%d blocks\n", 378 aux_info.sb->s_inodes_count - aux_info.sb->s_free_inodes_count, 379 aux_info.sb->s_inodes_count, 380 aux_info.sb->s_blocks_count_lo - aux_info.sb->s_free_blocks_count_lo, 381 aux_info.sb->s_blocks_count_lo); 382 383 write_ext4_image(fd, gzip, sparse, crc, wipe); 384 385 return 0; 386} 387