make_ext4fs.c revision 757ace516d8e4350616b5fd10da0c982d3d5ec74
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 24#include <dirent.h> 25#include <libgen.h> 26#include <stdio.h> 27#include <stdlib.h> 28#include <string.h> 29#include <unistd.h> 30#include <sys/stat.h> 31#include <sys/types.h> 32 33#ifdef ANDROID 34#include <private/android_filesystem_config.h> 35#endif 36 37/* TODO: Not implemented: 38 Allocating blocks in the same block group as the file inode 39 Hash or binary tree directories 40 Special files: sockets, devices, fifos 41 */ 42 43static int filter_dot(const struct dirent *d) 44{ 45 return (strcmp(d->d_name, "..") && strcmp(d->d_name, ".")); 46} 47 48static u32 build_default_directory_structure() 49{ 50 u32 inode; 51 u32 root_inode; 52 struct dentry dentries = { 53 .filename = "lost+found", 54 .file_type = EXT4_FT_DIR, 55 .mode = S_IRWXU, 56 .uid = 0, 57 .gid = 0, 58 .mtime = 0, 59 }; 60 root_inode = make_directory(0, 1, &dentries, 1); 61 inode = make_directory(root_inode, 0, NULL, 0); 62 *dentries.inode = inode; 63 inode_set_permissions(inode, dentries.mode, 64 dentries.uid, dentries.gid, dentries.mtime); 65 66 return root_inode; 67} 68 69/* Read a local directory and create the same tree in the generated filesystem. 70 Calls itself recursively with each directory in the given directory */ 71static u32 build_directory_structure(const char *full_path, const char *dir_path, 72 u32 dir_inode, int android) 73{ 74 int entries = 0; 75 struct dentry *dentries; 76 struct dirent **namelist; 77 struct stat stat; 78 int ret; 79 int i; 80 u32 inode; 81 u32 entry_inode; 82 u32 dirs = 0; 83 84 entries = scandir(full_path, &namelist, filter_dot, (void*)alphasort); 85 if (entries < 0) { 86 error_errno("scandir"); 87 return EXT4_ALLOCATE_FAILED; 88 } 89 90 dentries = calloc(entries, sizeof(struct dentry)); 91 if (dentries == NULL) 92 critical_error_errno("malloc"); 93 94 for (i = 0; i < entries; i++) { 95 dentries[i].filename = strdup(namelist[i]->d_name); 96 if (dentries[i].filename == NULL) 97 critical_error_errno("strdup"); 98 99 asprintf(&dentries[i].path, "%s/%s", dir_path, namelist[i]->d_name); 100 asprintf(&dentries[i].full_path, "%s/%s", full_path, namelist[i]->d_name); 101 102 free(namelist[i]); 103 104 ret = lstat(dentries[i].full_path, &stat); 105 if (ret < 0) { 106 error_errno("lstat"); 107 i--; 108 entries--; 109 continue; 110 } 111 112 dentries[i].size = stat.st_size; 113 dentries[i].mode = stat.st_mode & (S_ISUID|S_ISGID|S_ISVTX|S_IRWXU|S_IRWXG|S_IRWXO); 114 dentries[i].mtime = stat.st_mtime; 115 if (android) { 116#ifdef ANDROID 117 unsigned int mode = 0; 118 unsigned int uid = 0; 119 unsigned int gid = 0; 120 int dir = S_ISDIR(stat.st_mode); 121 fs_config(dentries[i].path, dir, &uid, &gid, &mode); 122 dentries[i].mode = mode; 123 dentries[i].uid = uid; 124 dentries[i].gid = gid; 125#else 126 error("can't set android permissions - built without android support"); 127#endif 128 } 129 130 if (S_ISREG(stat.st_mode)) { 131 dentries[i].file_type = EXT4_FT_REG_FILE; 132 } else if (S_ISDIR(stat.st_mode)) { 133 dentries[i].file_type = EXT4_FT_DIR; 134 dirs++; 135 } else if (S_ISCHR(stat.st_mode)) { 136 dentries[i].file_type = EXT4_FT_CHRDEV; 137 } else if (S_ISBLK(stat.st_mode)) { 138 dentries[i].file_type = EXT4_FT_BLKDEV; 139 } else if (S_ISFIFO(stat.st_mode)) { 140 dentries[i].file_type = EXT4_FT_FIFO; 141 } else if (S_ISSOCK(stat.st_mode)) { 142 dentries[i].file_type = EXT4_FT_SOCK; 143 } else if (S_ISLNK(stat.st_mode)) { 144 dentries[i].file_type = EXT4_FT_SYMLINK; 145 dentries[i].link = calloc(info.block_size, 1); 146 readlink(dentries[i].full_path, dentries[i].link, info.block_size - 1); 147 } else { 148 error("unknown file type on %s", dentries[i].path); 149 i--; 150 entries--; 151 } 152 } 153 free(namelist); 154 155 inode = make_directory(dir_inode, entries, dentries, dirs); 156 157 for (i = 0; i < entries; i++) { 158 if (dentries[i].file_type == EXT4_FT_REG_FILE) { 159 entry_inode = make_file(dentries[i].full_path, dentries[i].size); 160 } else if (dentries[i].file_type == EXT4_FT_DIR) { 161 entry_inode = build_directory_structure(dentries[i].full_path, 162 dentries[i].path, inode, android); 163 } else if (dentries[i].file_type == EXT4_FT_SYMLINK) { 164 entry_inode = make_link(dentries[i].full_path, dentries[i].link); 165 } else { 166 error("unknown file type on %s", dentries[i].path); 167 entry_inode = 0; 168 } 169 *dentries[i].inode = entry_inode; 170 171 ret = inode_set_permissions(entry_inode, dentries[i].mode, 172 dentries[i].uid, dentries[i].gid, 173 dentries[i].mtime); 174 if (ret) 175 error("failed to set permissions on %s\n", dentries[i].path); 176 177 free(dentries[i].path); 178 free(dentries[i].full_path); 179 free(dentries[i].link); 180 free((void *)dentries[i].filename); 181 } 182 183 free(dentries); 184 return inode; 185} 186 187static u32 compute_block_size() 188{ 189 return 4096; 190} 191 192static u32 compute_journal_blocks() 193{ 194 u32 journal_blocks = DIV_ROUND_UP(info.len, info.block_size) / 64; 195 if (journal_blocks < 1024) 196 journal_blocks = 1024; 197 if (journal_blocks > 32768) 198 journal_blocks = 32768; 199 return journal_blocks; 200} 201 202static u32 compute_blocks_per_group() 203{ 204 return info.block_size * 8; 205} 206 207static u32 compute_inodes() 208{ 209 return DIV_ROUND_UP(info.len, info.block_size) / 4; 210} 211 212static u32 compute_inodes_per_group() 213{ 214 u32 blocks = DIV_ROUND_UP(info.len, info.block_size); 215 u32 block_groups = DIV_ROUND_UP(blocks, info.blocks_per_group); 216 return DIV_ROUND_UP(info.inodes, block_groups); 217} 218 219static u32 compute_bg_desc_reserve_blocks() 220{ 221 u32 blocks = DIV_ROUND_UP(info.len, info.block_size); 222 u32 block_groups = DIV_ROUND_UP(blocks, info.blocks_per_group); 223 u32 bg_desc_blocks = DIV_ROUND_UP(block_groups * sizeof(struct ext2_group_desc), 224 info.block_size); 225 226 u32 bg_desc_reserve_blocks = 227 DIV_ROUND_UP(block_groups * 1024 * sizeof(struct ext2_group_desc), 228 info.block_size) - bg_desc_blocks; 229 230 if (bg_desc_reserve_blocks > info.block_size / sizeof(u32)) 231 bg_desc_reserve_blocks = info.block_size / sizeof(u32); 232 233 return bg_desc_reserve_blocks; 234} 235 236void reset_ext4fs_info() { 237 // Reset all the global data structures used by make_ext4fs so it 238 // can be called again. 239 memset(&info, 0, sizeof(info)); 240 memset(&aux_info, 0, sizeof(aux_info)); 241 free_data_blocks(); 242} 243 244int make_ext4fs(const char *filename, const char *directory, 245 char *mountpoint, int android, int gzip, int sparse, 246 int crc) 247{ 248 u32 root_inode_num; 249 u16 root_mode; 250 251 if (info.len == 0) 252 info.len = get_file_size(filename); 253 254 if (info.len <= 0) { 255 fprintf(stderr, "Need size of filesystem\n"); 256 return EXIT_FAILURE; 257 } 258 259 if (info.block_size <= 0) 260 info.block_size = compute_block_size(); 261 262 if (info.journal_blocks == 0) 263 info.journal_blocks = compute_journal_blocks(); 264 265 if (info.no_journal == 0) 266 info.feat_compat = EXT4_FEATURE_COMPAT_HAS_JOURNAL; 267 else 268 info.journal_blocks = 0; 269 270 if (info.blocks_per_group <= 0) 271 info.blocks_per_group = compute_blocks_per_group(); 272 273 if (info.inodes <= 0) 274 info.inodes = compute_inodes(); 275 276 if (info.inode_size <= 0) 277 info.inode_size = 256; 278 279 if (info.label == NULL) 280 info.label = ""; 281 282 info.inodes_per_group = compute_inodes_per_group(); 283 284 info.feat_compat |= 285 EXT4_FEATURE_COMPAT_RESIZE_INODE; 286 287 info.feat_ro_compat |= 288 EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER | 289 EXT4_FEATURE_RO_COMPAT_LARGE_FILE; 290 291 info.feat_incompat |= 292 EXT4_FEATURE_INCOMPAT_EXTENTS | 293 EXT4_FEATURE_INCOMPAT_FILETYPE; 294 295 296 info.bg_desc_reserve_blocks = compute_bg_desc_reserve_blocks(); 297 298 printf("Creating filesystem with parameters:\n"); 299 printf(" Size: %llu\n", info.len); 300 printf(" Block size: %d\n", info.block_size); 301 printf(" Blocks per group: %d\n", info.blocks_per_group); 302 printf(" Inodes per group: %d\n", info.inodes_per_group); 303 printf(" Inode size: %d\n", info.inode_size); 304 printf(" Journal blocks: %d\n", info.journal_blocks); 305 printf(" Label: %s\n", info.label); 306 307 ext4_create_fs_aux_info(); 308 309 printf(" Blocks: %llu\n", aux_info.len_blocks); 310 printf(" Block groups: %d\n", aux_info.groups); 311 printf(" Reserved block group size: %d\n", info.bg_desc_reserve_blocks); 312 313 block_allocator_init(); 314 315 ext4_fill_in_sb(); 316 317 if (reserve_inodes(0, 10) == EXT4_ALLOCATE_FAILED) 318 error("failed to reserve first 10 inodes"); 319 320 if (info.feat_compat & EXT4_FEATURE_COMPAT_HAS_JOURNAL) 321 ext4_create_journal_inode(); 322 323 if (info.feat_compat & EXT4_FEATURE_COMPAT_RESIZE_INODE) 324 ext4_create_resize_inode(); 325 326 if (directory) 327 root_inode_num = build_directory_structure(directory, mountpoint, 0, android); 328 else 329 root_inode_num = build_default_directory_structure(); 330 331 root_mode = S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH; 332 inode_set_permissions(root_inode_num, root_mode, 0, 0, 0); 333 334 ext4_update_free(); 335 336 ext4_queue_sb(); 337 338 printf("Created filesystem with %d/%d inodes and %d/%d blocks\n", 339 aux_info.sb->s_inodes_count - aux_info.sb->s_free_inodes_count, 340 aux_info.sb->s_inodes_count, 341 aux_info.sb->s_blocks_count_lo - aux_info.sb->s_free_blocks_count_lo, 342 aux_info.sb->s_blocks_count_lo); 343 344 write_ext4_image(filename, gzip, sparse, crc); 345 346 return 0; 347} 348