ext4_utils/make_ext4fs.c

   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 #define _GNU_SOURCE
  18
  19 #include <dirent.h>
  20 #include <libgen.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <unistd.h>
  25 #include <sys/stat.h>
  26 #include <sys/types.h>
  27
  28 #include "make_ext4fs.h"
  29 #include "output_file.h"
  30 #include "ext4_utils.h"
  31 #include "allocate.h"
  32 #include "contents.h"
  33 #include "uuid.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
  45 static int filter_dot(const struct dirent *d)
  46 {
  47         return (strcmp(d->d_name, "..") && strcmp(d->d_name, "."));
  48 }
  49
  50 static 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         };
  61         root_inode = make_directory(0, 1, &dentries, 1);
  62         inode = make_directory(root_inode, 0, NULL, 0);
  63         *dentries.inode = inode;
  64
  65         return root_inode;
  66 }
  67
  68 /* Read a local directory and create the same tree in the generated filesystem.
  69    Calls itself recursively with each directory in the given directory */
  70 static u32 build_directory_structure(const char *full_path, const char *dir_path,
  71                 u32 dir_inode, int android)
  72 {
  73         int entries = 0;
  74         struct dentry *dentries;
  75         struct dirent **namelist;
  76         struct stat stat;
  77         int ret;
  78         int i;
  79         u32 inode;
  80         u32 entry_inode;
  81         u32 dirs = 0;
  82
  83         entries = scandir(full_path, &namelist, filter_dot, (void*)alphasort);
  84         if (entries < 0) {
  85                 error_errno("scandir");
  86                 return EXT4_ALLOCATE_FAILED;
  87         }
  88
  89         dentries = calloc(entries, sizeof(struct dentry));
  90         if (dentries == NULL)
  91                 critical_error_errno("malloc");
  92
  93         for (i = 0; i < entries; i++) {
  94                 dentries[i].filename = strdup(namelist[i]->d_name);
  95                 if (dentries[i].filename == NULL)
  96                         critical_error_errno("strdup");
  97
  98                 asprintf(&dentries[i].path, "%s/%s", dir_path, namelist[i]->d_name);
  99                 asprintf(&dentries[i].full_path, "%s/%s", full_path, namelist[i]->d_name);
 100
 101                 free(namelist[i]);
 102
 103                 ret = lstat(dentries[i].full_path, &stat);
 104                 if (ret < 0) {
 105                         error_errno("lstat");
 106                         i--;
 107                         entries--;
 108                         continue;
 109                 }
 110
 111                 dentries[i].size = stat.st_size;
 112                 dentries[i].mode = stat.st_mode & (S_ISUID|S_ISGID|S_ISVTX|S_IRWXU|S_IRWXG|S_IRWXO);
 113                 if (android) {
 114 #ifdef ANDROID
 115                         unsigned int mode = 0;
 116                         unsigned int uid = 0;
 117                         unsigned int gid = 0;
 118                         int dir = S_ISDIR(stat.st_mode);
 119                         fs_config(dentries[i].path, dir, &uid, &gid, &mode);
 120                         dentries[i].mode = mode;
 121                         dentries[i].uid = uid;
 122                         dentries[i].gid = gid;
 123 #else
 124                         error("can't set android permissions - built without android support");
 125 #endif
 126                 }
 127
 128                 if (S_ISREG(stat.st_mode)) {
 129                         dentries[i].file_type = EXT4_FT_REG_FILE;
 130                 } else if (S_ISDIR(stat.st_mode)) {
 131                         dentries[i].file_type = EXT4_FT_DIR;
 132                         dirs++;
 133                 } else if (S_ISCHR(stat.st_mode)) {
 134                         dentries[i].file_type = EXT4_FT_CHRDEV;
 135                 } else if (S_ISBLK(stat.st_mode)) {
 136                         dentries[i].file_type = EXT4_FT_BLKDEV;
 137                 } else if (S_ISFIFO(stat.st_mode)) {
 138                         dentries[i].file_type = EXT4_FT_FIFO;
 139                 } else if (S_ISSOCK(stat.st_mode)) {
 140                         dentries[i].file_type = EXT4_FT_SOCK;
 141                 } else if (S_ISLNK(stat.st_mode)) {
 142                         dentries[i].file_type = EXT4_FT_SYMLINK;
 143                         dentries[i].link = calloc(info.block_size, 1);
 144                         readlink(dentries[i].full_path, dentries[i].link, info.block_size - 1);
 145                 } else {
 146                         error("unknown file type on %s", dentries[i].path);
 147                         i--;
 148                         entries--;
 149                 }
 150         }
 151         free(namelist);
 152
 153         inode = make_directory(dir_inode, entries, dentries, dirs);
 154
 155         for (i = 0; i < entries; i++) {
 156                 if (dentries[i].file_type == EXT4_FT_REG_FILE) {
 157                         entry_inode = make_file(dentries[i].full_path, dentries[i].size);
 158                 } else if (dentries[i].file_type == EXT4_FT_DIR) {
 159                         entry_inode = build_directory_structure(dentries[i].full_path,
 160                                         dentries[i].path, inode, android);
 161                 } else if (dentries[i].file_type == EXT4_FT_SYMLINK) {
 162                         entry_inode = make_link(dentries[i].full_path, dentries[i].link);
 163                 } else {
 164                         error("unknown file type on %s", dentries[i].path);
 165                         entry_inode = 0;
 166                 }
 167                 *dentries[i].inode = entry_inode;
 168
 169                 ret = inode_set_permissions(entry_inode, dentries[i].mode,
 170                                 dentries[i].uid, dentries[i].gid);
 171                 if (ret)
 172                         error("failed to set permissions on %s\n", dentries[i].path);
 173
 174                 free(dentries[i].path);
 175                 free(dentries[i].full_path);
 176                 free(dentries[i].link);
 177                 free((void *)dentries[i].filename);
 178         }
 179
 180         free(dentries);
 181         return inode;
 182 }
 183
 184 static u32 compute_block_size()
 185 {
 186         return 4096;
 187 }
 188
 189 static u32 compute_blocks_per_group()
 190 {
 191         return info.block_size * 8;
 192 }
 193
 194 static u32 compute_inodes()
 195 {
 196         return DIV_ROUND_UP(info.len, info.block_size) / 4;
 197 }
 198
 199 static u32 compute_inodes_per_group()
 200 {
 201         u32 blocks = DIV_ROUND_UP(info.len, info.block_size);
 202         u32 block_groups = DIV_ROUND_UP(blocks, info.blocks_per_group);
 203         return DIV_ROUND_UP(info.inodes, block_groups);
 204 }
 205
 206 static void usage(char *path)
 207 {
 208         fprintf(stderr, "%s [ -l <len> ] [ -j <journal size> ] [ -b <block_size> ]\n", basename(path));
 209         fprintf(stderr, "    [ -g <blocks per group> ] [ -i <inodes> ] [ -I <inode size> ]\n");
 210         fprintf(stderr, "    [ -L <label> ] [ -f ] [ -a <android mountpoint> ]\n");
 211         fprintf(stderr, "    <filename> [<directory>]\n");
 212 }
 213
 214 int main(int argc, char **argv)
 215 {
 216         int opt;
 217         const char *filename = NULL;
 218         const char *directory = NULL;
 219         char *mountpoint = "";
 220         int android = 0;
 221         int gzip = 0;
 222         u32 root_inode_num;
 223         u16 root_mode;
 224
 225         while ((opt = getopt(argc, argv, "l:j:b:g:i:I:L:a:fz")) != -1) {
 226                 switch (opt) {
 227                 case 'l':
 228                         info.len = parse_num(optarg);
 229                         break;
 230                 case 'j':
 231                         info.journal_blocks = parse_num(optarg);
 232                         break;
 233                 case 'b':
 234                         info.block_size = parse_num(optarg);
 235                         break;
 236                 case 'g':
 237                         info.blocks_per_group = parse_num(optarg);
 238                         break;
 239                 case 'i':
 240                         info.inodes = parse_num(optarg);
 241                         break;
 242                 case 'I':
 243                         info.inode_size = parse_num(optarg);
 244                         break;
 245                 case 'L':
 246                         info.label = optarg;
 247                         break;
 248                 case 'f':
 249                         force = 1;
 250                         break;
 251                 case 'a':
 252                         android = 1;
 253                         mountpoint = optarg;
 254                         break;
 255                 case 'z':
 256                         gzip = 1;
 257                         break;
 258                 default: /* '?' */
 259                         usage(argv[0]);
 260                         exit(EXIT_FAILURE);
 261                 }
 262         }
 263
 264         if (optind >= argc) {
 265                 fprintf(stderr, "Expected filename after options\n");
 266                 usage(argv[0]);
 267                 exit(EXIT_FAILURE);
 268         }
 269
 270         filename = argv[optind++];
 271
 272         if (optind < argc)
 273                 directory = argv[optind++];
 274
 275         if (optind < argc) {
 276                 fprintf(stderr, "Unexpected argument: %s\n", argv[optind]);
 277                 usage(argv[0]);
 278                 exit(EXIT_FAILURE);
 279         }
 280
 281         if (info.len == 0)
 282                 info.len = get_file_size(filename);
 283
 284         if (info.len <= 0) {
 285                 fprintf(stderr, "Need size of filesystem\n");
 286                 usage(argv[0]);
 287                 exit(EXIT_FAILURE);
 288         }
 289
 290         if (info.journal_blocks > 0)
 291                 info.feat_compat = EXT4_FEATURE_COMPAT_HAS_JOURNAL;
 292
 293         if (info.block_size <= 0)
 294                 info.block_size = compute_block_size();
 295
 296         if (info.blocks_per_group <= 0)
 297                 info.blocks_per_group = compute_blocks_per_group();
 298
 299         if (info.inodes <= 0)
 300                 info.inodes = compute_inodes();
 301
 302         if (info.inode_size <= 0)
 303                 info.inode_size = 256;
 304
 305         if (info.label == NULL)
 306                 info.label = "";
 307
 308         info.inodes_per_group = compute_inodes_per_group();
 309
 310         info.feat_compat |=
 311                         EXT4_FEATURE_COMPAT_RESIZE_INODE;
 312
 313         info.feat_ro_compat |=
 314                         EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER |
 315                         EXT4_FEATURE_RO_COMPAT_LARGE_FILE;
 316
 317         info.feat_incompat |=
 318                         EXT4_FEATURE_INCOMPAT_EXTENTS |
 319                         EXT4_FEATURE_INCOMPAT_FILETYPE;
 320
 321
 322         printf("Creating filesystem with parameters:\n");
 323         printf("    Size: %llu\n", info.len);
 324         printf("    Block size: %d\n", info.block_size);
 325         printf("    Blocks per group: %d\n", info.blocks_per_group);
 326         printf("    Inodes per group: %d\n", info.inodes_per_group);
 327         printf("    Inode size: %d\n", info.inode_size);
 328         printf("    Label: %s\n", info.label);
 329
 330         ext4_create_fs_aux_info();
 331
 332         printf("    Blocks: %llu\n", aux_info.len_blocks);
 333         printf("    Block groups: %d\n", aux_info.groups);
 334         printf("    Reserved block group size: %d\n", aux_info.bg_desc_reserve_blocks);
 335
 336         block_allocator_init();
 337
 338         ext4_fill_in_sb();
 339
 340         if (reserve_inodes(0, 10) == EXT4_ALLOCATE_FAILED)
 341                 error("failed to reserve first 10 inodes");
 342
 343         if (info.feat_compat & EXT4_FEATURE_COMPAT_HAS_JOURNAL)
 344                 ext4_create_journal_inode();
 345
 346         if (info.feat_compat & EXT4_FEATURE_COMPAT_RESIZE_INODE)
 347                 ext4_create_resize_inode();
 348
 349         if (directory)
 350                 root_inode_num = build_directory_structure(directory, mountpoint, 0, android);
 351         else
 352                 root_inode_num = build_default_directory_structure();
 353
 354         root_mode = S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH;
 355         inode_set_permissions(root_inode_num, root_mode, 0, 0);
 356
 357         ext4_update_free();
 358
 359         printf("Created filesystem with %d/%d inodes and %d/%d blocks\n",
 360                         aux_info.sb->s_inodes_count - aux_info.sb->s_free_inodes_count,
 361                         aux_info.sb->s_inodes_count,
 362                         aux_info.sb->s_blocks_count_lo - aux_info.sb->s_free_blocks_count_lo,
 363                         aux_info.sb->s_blocks_count_lo);
 364
 365         write_ext4_image(filename, gzip);
 366
 367         return 0;
 368 }