make_ext4fs.c revision 8642b7fba54727a38f751516bcdc452fb09ef610
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 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 return DIV_ROUND_UP(info.inodes, block_groups); 219} 220 221void reset_ext4fs_info() { 222 // Reset all the global data structures used by make_ext4fs so it 223 // can be called again. 224 memset(&info, 0, sizeof(info)); 225 memset(&aux_info, 0, sizeof(aux_info)); 226 free_data_blocks(); 227} 228 229int make_ext4fs(const char *filename, const char *directory, 230 char *mountpoint, int android, int gzip, int sparse) 231{ 232 u32 root_inode_num; 233 u16 root_mode; 234 235 if (info.len == 0) 236 info.len = get_file_size(filename); 237 238 if (info.len <= 0) { 239 fprintf(stderr, "Need size of filesystem\n"); 240 return EXIT_FAILURE; 241 } 242 243 if (info.block_size <= 0) 244 info.block_size = compute_block_size(); 245 246 if (info.journal_blocks == 0) 247 info.journal_blocks = compute_journal_blocks(); 248 249 if (info.no_journal == 0) 250 info.feat_compat = EXT4_FEATURE_COMPAT_HAS_JOURNAL; 251 else 252 info.journal_blocks = 0; 253 254 if (info.blocks_per_group <= 0) 255 info.blocks_per_group = compute_blocks_per_group(); 256 257 if (info.inodes <= 0) 258 info.inodes = compute_inodes(); 259 260 if (info.inode_size <= 0) 261 info.inode_size = 256; 262 263 if (info.label == NULL) 264 info.label = ""; 265 266 info.inodes_per_group = compute_inodes_per_group(); 267 268 info.feat_compat |= 269 EXT4_FEATURE_COMPAT_RESIZE_INODE; 270 271 info.feat_ro_compat |= 272 EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER | 273 EXT4_FEATURE_RO_COMPAT_LARGE_FILE; 274 275 info.feat_incompat |= 276 EXT4_FEATURE_INCOMPAT_EXTENTS | 277 EXT4_FEATURE_INCOMPAT_FILETYPE; 278 279 280 printf("Creating filesystem with parameters:\n"); 281 printf(" Size: %llu\n", info.len); 282 printf(" Block size: %d\n", info.block_size); 283 printf(" Blocks per group: %d\n", info.blocks_per_group); 284 printf(" Inodes per group: %d\n", info.inodes_per_group); 285 printf(" Inode size: %d\n", info.inode_size); 286 printf(" Journal blocks: %d\n", info.journal_blocks); 287 printf(" Label: %s\n", info.label); 288 289 ext4_create_fs_aux_info(); 290 291 printf(" Blocks: %llu\n", aux_info.len_blocks); 292 printf(" Block groups: %d\n", aux_info.groups); 293 printf(" Reserved block group size: %d\n", aux_info.bg_desc_reserve_blocks); 294 295 block_allocator_init(); 296 297 ext4_fill_in_sb(); 298 299 if (reserve_inodes(0, 10) == EXT4_ALLOCATE_FAILED) 300 error("failed to reserve first 10 inodes"); 301 302 if (info.feat_compat & EXT4_FEATURE_COMPAT_HAS_JOURNAL) 303 ext4_create_journal_inode(); 304 305 if (info.feat_compat & EXT4_FEATURE_COMPAT_RESIZE_INODE) 306 ext4_create_resize_inode(); 307 308 if (directory) 309 root_inode_num = build_directory_structure(directory, mountpoint, 0, android); 310 else 311 root_inode_num = build_default_directory_structure(); 312 313 root_mode = S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH; 314 inode_set_permissions(root_inode_num, root_mode, 0, 0, 0); 315 316 ext4_update_free(); 317 318 printf("Created filesystem with %d/%d inodes and %d/%d blocks\n", 319 aux_info.sb->s_inodes_count - aux_info.sb->s_free_inodes_count, 320 aux_info.sb->s_inodes_count, 321 aux_info.sb->s_blocks_count_lo - aux_info.sb->s_free_blocks_count_lo, 322 aux_info.sb->s_blocks_count_lo); 323 324 write_ext4_image(filename, gzip, sparse); 325 326 return 0; 327} 328