2 * Copyright (C) 2010 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 #include "make_ext4fs.h"
18 #include "ext4_utils.h"
24 #include <sparse/sparse.h>
36 #include <sys/types.h>
44 /* TODO: Not implemented:
45 Allocating blocks in the same block group as the file inode
46 Hash or binary tree directories
47 Special files: sockets, devices, fifos
50 static int filter_dot(const struct dirent
*d
)
52 return (strcmp(d
->d_name
, "..") && strcmp(d
->d_name
, "."));
55 static u32
build_default_directory_structure(const char *dir_path
)
59 struct dentry dentries
= {
60 .filename
= "lost+found",
61 .file_type
= EXT4_FT_DIR
,
67 root_inode
= make_directory(0, 1, &dentries
, 1);
68 inode
= make_directory(root_inode
, 0, NULL
, 0);
69 *dentries
.inode
= inode
;
70 inode_set_permissions(inode
, dentries
.mode
,
71 dentries
.uid
, dentries
.gid
, dentries
.mtime
);
77 /* Read a local directory and create the same tree in the generated filesystem.
78 Calls itself recursively with each directory in the given directory.
79 full_path is an absolute or relative path, with a trailing slash, to the
80 directory on disk that should be copied, or NULL if this is a directory
81 that does not exist on disk (e.g. lost+found).
82 dir_path is an absolute path, with trailing slash, to the same directory
83 if the image were mounted at the specified mount point */
84 static u32
build_directory_structure(const char *full_path
, const char *dir_path
,
85 u32 dir_inode
, fs_config_func_t fs_config_func
,
86 int verbose
, time_t fixed_time
)
89 struct dentry
*dentries
;
90 struct dirent
**namelist
= NULL
;
97 bool needs_lost_and_found
= false;
100 entries
= scandir(full_path
, &namelist
, filter_dot
, (void*)alphasort
);
103 /* The scandir function implemented in glibc has a bug that makes it
104 erroneously fail with ENOMEM under certain circumstances.
105 As a workaround we can retry the scandir call with the same arguments.
106 GLIBC BZ: https://sourceware.org/bugzilla/show_bug.cgi?id=17804 */
108 entries
= scandir(full_path
, &namelist
, filter_dot
, (void*)alphasort
);
111 error_errno("scandir");
112 return EXT4_ALLOCATE_FAILED
;
117 if (dir_inode
== 0) {
118 /* root directory, check if lost+found already exists */
119 for (i
= 0; i
< entries
; i
++)
120 if (strcmp(namelist
[i
]->d_name
, "lost+found") == 0)
123 needs_lost_and_found
= true;
126 dentries
= calloc(entries
, sizeof(struct dentry
));
127 if (dentries
== NULL
)
128 critical_error_errno("malloc");
130 for (i
= 0; i
< entries
; i
++) {
131 dentries
[i
].filename
= strdup(namelist
[i
]->d_name
);
132 if (dentries
[i
].filename
== NULL
)
133 critical_error_errno("strdup");
135 asprintf(&dentries
[i
].path
, "%s%s", dir_path
, namelist
[i
]->d_name
);
136 asprintf(&dentries
[i
].full_path
, "%s%s", full_path
, namelist
[i
]->d_name
);
140 ret
= lstat(dentries
[i
].full_path
, &stat
);
142 error_errno("lstat");
148 dentries
[i
].size
= stat
.st_size
;
149 dentries
[i
].mode
= stat
.st_mode
& (S_ISUID
|S_ISGID
|S_ISVTX
|S_IRWXU
|S_IRWXG
|S_IRWXO
);
150 if (fixed_time
== -1) {
151 dentries
[i
].mtime
= stat
.st_mtime
;
153 dentries
[i
].mtime
= fixed_time
;
155 uint64_t capabilities
;
156 if (fs_config_func
!= NULL
) {
158 unsigned int mode
= 0;
159 unsigned int uid
= 0;
160 unsigned int gid
= 0;
161 int dir
= S_ISDIR(stat
.st_mode
);
162 fs_config_func(dentries
[i
].path
, dir
, &uid
, &gid
, &mode
, &capabilities
);
163 dentries
[i
].mode
= mode
;
164 dentries
[i
].uid
= uid
;
165 dentries
[i
].gid
= gid
;
166 dentries
[i
].capabilities
= capabilities
;
168 error("can't set android permissions - built without android support");
172 if (S_ISREG(stat
.st_mode
)) {
173 dentries
[i
].file_type
= EXT4_FT_REG_FILE
;
174 } else if (S_ISDIR(stat
.st_mode
)) {
175 dentries
[i
].file_type
= EXT4_FT_DIR
;
177 } else if (S_ISCHR(stat
.st_mode
)) {
178 dentries
[i
].file_type
= EXT4_FT_CHRDEV
;
179 } else if (S_ISBLK(stat
.st_mode
)) {
180 dentries
[i
].file_type
= EXT4_FT_BLKDEV
;
181 } else if (S_ISFIFO(stat
.st_mode
)) {
182 dentries
[i
].file_type
= EXT4_FT_FIFO
;
183 } else if (S_ISSOCK(stat
.st_mode
)) {
184 dentries
[i
].file_type
= EXT4_FT_SOCK
;
185 } else if (S_ISLNK(stat
.st_mode
)) {
186 dentries
[i
].file_type
= EXT4_FT_SYMLINK
;
187 dentries
[i
].link
= calloc(info
.block_size
, 1);
188 readlink(dentries
[i
].full_path
, dentries
[i
].link
, info
.block_size
- 1);
190 error("unknown file type on %s", dentries
[i
].path
);
197 if (needs_lost_and_found
) {
198 /* insert a lost+found directory at the beginning of the dentries */
199 struct dentry
*tmp
= calloc(entries
+ 1, sizeof(struct dentry
));
200 memset(tmp
, 0, sizeof(struct dentry
));
201 memcpy(tmp
+ 1, dentries
, entries
* sizeof(struct dentry
));
204 dentries
[0].filename
= strdup("lost+found");
205 asprintf(&dentries
[0].path
, "%slost+found", dir_path
);
206 dentries
[0].full_path
= NULL
;
207 dentries
[0].size
= 0;
208 dentries
[0].mode
= S_IRWXU
;
209 dentries
[0].file_type
= EXT4_FT_DIR
;
216 inode
= make_directory(dir_inode
, entries
, dentries
, dirs
);
218 for (i
= 0; i
< entries
; i
++) {
219 if (dentries
[i
].file_type
== EXT4_FT_REG_FILE
) {
220 entry_inode
= make_file(dentries
[i
].full_path
, dentries
[i
].size
);
221 } else if (dentries
[i
].file_type
== EXT4_FT_DIR
) {
222 char *subdir_full_path
= NULL
;
223 char *subdir_dir_path
;
224 if (dentries
[i
].full_path
) {
225 ret
= asprintf(&subdir_full_path
, "%s/", dentries
[i
].full_path
);
227 critical_error_errno("asprintf");
229 ret
= asprintf(&subdir_dir_path
, "%s/", dentries
[i
].path
);
231 critical_error_errno("asprintf");
232 entry_inode
= build_directory_structure(subdir_full_path
,
233 subdir_dir_path
, inode
, fs_config_func
, verbose
, fixed_time
);
234 free(subdir_full_path
);
235 free(subdir_dir_path
);
236 } else if (dentries
[i
].file_type
== EXT4_FT_SYMLINK
) {
237 entry_inode
= make_link(dentries
[i
].link
);
239 error("unknown file type on %s", dentries
[i
].path
);
242 *dentries
[i
].inode
= entry_inode
;
244 ret
= inode_set_permissions(entry_inode
, dentries
[i
].mode
,
245 dentries
[i
].uid
, dentries
[i
].gid
,
248 error("failed to set permissions on %s\n", dentries
[i
].path
);
251 * It's important to call inode_set_selinux() before
252 * inode_set_capabilities(). Extended attributes need to
253 * be stored sorted order, and we guarantee this by making
254 * the calls in the proper order.
255 * Please see xattr_assert_sane() in contents.c
257 ret
= inode_set_selinux(entry_inode
, dentries
[i
].secon
);
259 error("failed to set SELinux context on %s\n", dentries
[i
].path
);
260 ret
= inode_set_capabilities(entry_inode
, dentries
[i
].capabilities
);
262 error("failed to set capability on %s\n", dentries
[i
].path
);
264 free(dentries
[i
].path
);
265 free(dentries
[i
].full_path
);
266 free(dentries
[i
].link
);
267 free((void *)dentries
[i
].filename
);
268 free(dentries
[i
].secon
);
276 static u32
compute_block_size()
281 static u32
compute_journal_blocks()
283 u32 journal_blocks
= DIV_ROUND_UP(info
.len
, info
.block_size
) / 64;
284 if (journal_blocks
< 1024)
285 journal_blocks
= 1024;
286 if (journal_blocks
> 32768)
287 journal_blocks
= 32768;
288 return journal_blocks
;
291 static u32
compute_blocks_per_group()
293 return info
.block_size
* 8;
296 static u32
compute_inodes()
298 return DIV_ROUND_UP(info
.len
, info
.block_size
) / 4;
301 static u32
compute_inodes_per_group()
303 u32 blocks
= DIV_ROUND_UP(info
.len
, info
.block_size
);
304 u32 block_groups
= DIV_ROUND_UP(blocks
, info
.blocks_per_group
);
305 u32 inodes
= DIV_ROUND_UP(info
.inodes
, block_groups
);
306 inodes
= EXT4_ALIGN(inodes
, (info
.block_size
/ info
.inode_size
));
308 /* After properly rounding up the number of inodes/group,
309 * make sure to update the total inodes field in the info struct.
311 info
.inodes
= inodes
* block_groups
;
316 static u32
compute_bg_desc_reserve_blocks()
318 u32 blocks
= DIV_ROUND_UP(info
.len
, info
.block_size
);
319 u32 block_groups
= DIV_ROUND_UP(blocks
, info
.blocks_per_group
);
320 u32 bg_desc_blocks
= DIV_ROUND_UP(block_groups
* sizeof(struct ext2_group_desc
),
323 u32 bg_desc_reserve_blocks
=
324 DIV_ROUND_UP(block_groups
* 1024 * sizeof(struct ext2_group_desc
),
325 info
.block_size
) - bg_desc_blocks
;
327 if (bg_desc_reserve_blocks
> info
.block_size
/ sizeof(u32
))
328 bg_desc_reserve_blocks
= info
.block_size
/ sizeof(u32
);
330 return bg_desc_reserve_blocks
;
333 void reset_ext4fs_info() {
334 // Reset all the global data structures used by make_ext4fs so it
335 // can be called again.
336 memset(&info
, 0, sizeof(info
));
337 memset(&aux_info
, 0, sizeof(aux_info
));
339 if (ext4_sparse_file
) {
340 sparse_file_destroy(ext4_sparse_file
);
341 ext4_sparse_file
= NULL
;
345 int make_ext4fs_sparse_fd(int fd
, long long len
,
346 const char *mountpoint
)
351 return make_ext4fs_internal(fd
, NULL
, mountpoint
, NULL
, 0, 1, 0, 0, 0, -1, NULL
);
354 int make_ext4fs(const char *filename
, long long len
,
355 const char *mountpoint
)
363 fd
= open(filename
, O_WRONLY
| O_CREAT
| O_TRUNC
| O_BINARY
, 0644);
369 status
= make_ext4fs_internal(fd
, NULL
, mountpoint
, NULL
, 0, 0, 0, 1, 0, -1, NULL
);
375 /* return a newly-malloc'd string that is a copy of str. The new string
376 is guaranteed to have a trailing slash. If absolute is true, the new string
377 is also guaranteed to have a leading slash.
379 static char *canonicalize_slashes(const char *str
, bool absolute
)
382 int len
= strlen(str
);
393 if (str
[0] != '/' && absolute
) {
396 if (str
[len
- 1] != '/') {
399 ret
= malloc(newlen
+ 1);
401 critical_error("malloc");
405 if (str
[0] != '/' && absolute
) {
412 if (str
[len
- 1] != '/') {
416 if (ptr
!= ret
+ newlen
) {
417 critical_error("assertion failed\n");
425 static char *canonicalize_abs_slashes(const char *str
)
427 return canonicalize_slashes(str
, true);
430 static char *canonicalize_rel_slashes(const char *str
)
432 return canonicalize_slashes(str
, false);
435 int make_ext4fs_internal(int fd
, const char *_directory
,
436 const char *_mountpoint
, fs_config_func_t fs_config_func
, int gzip
,
437 int sparse
, int crc
, int wipe
,
438 int verbose
, time_t fixed_time
,
439 FILE* block_list_file
)
444 char *directory
= NULL
;
446 if (setjmp(setjmp_env
))
447 return EXIT_FAILURE
; /* Handle a call to longjmp() */
449 if (_mountpoint
== NULL
) {
450 mountpoint
= strdup("");
452 mountpoint
= canonicalize_abs_slashes(_mountpoint
);
456 directory
= canonicalize_rel_slashes(_directory
);
460 info
.len
= get_file_size(fd
);
463 fprintf(stderr
, "Need size of filesystem\n");
467 if (info
.block_size
<= 0)
468 info
.block_size
= compute_block_size();
470 /* Round down the filesystem length to be a multiple of the block size */
471 info
.len
&= ~((u64
)info
.block_size
- 1);
473 if (info
.journal_blocks
== 0)
474 info
.journal_blocks
= compute_journal_blocks();
476 if (info
.no_journal
== 0)
477 info
.feat_compat
= EXT4_FEATURE_COMPAT_HAS_JOURNAL
;
479 info
.journal_blocks
= 0;
481 if (info
.blocks_per_group
<= 0)
482 info
.blocks_per_group
= compute_blocks_per_group();
484 if (info
.inodes
<= 0)
485 info
.inodes
= compute_inodes();
487 if (info
.inode_size
<= 0)
488 info
.inode_size
= 256;
490 if (info
.label
== NULL
)
493 info
.inodes_per_group
= compute_inodes_per_group();
496 EXT4_FEATURE_COMPAT_RESIZE_INODE
|
497 EXT4_FEATURE_COMPAT_EXT_ATTR
;
499 info
.feat_ro_compat
|=
500 EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER
|
501 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
|
502 EXT4_FEATURE_RO_COMPAT_GDT_CSUM
;
504 info
.feat_incompat
|=
505 EXT4_FEATURE_INCOMPAT_EXTENTS
|
506 EXT4_FEATURE_INCOMPAT_FILETYPE
;
509 info
.bg_desc_reserve_blocks
= compute_bg_desc_reserve_blocks();
511 printf("Creating filesystem with parameters:\n");
512 printf(" Size: %"PRIu64
"\n", info
.len
);
513 printf(" Block size: %d\n", info
.block_size
);
514 printf(" Blocks per group: %d\n", info
.blocks_per_group
);
515 printf(" Inodes per group: %d\n", info
.inodes_per_group
);
516 printf(" Inode size: %d\n", info
.inode_size
);
517 printf(" Journal blocks: %d\n", info
.journal_blocks
);
518 printf(" Label: %s\n", info
.label
);
520 ext4_create_fs_aux_info();
522 printf(" Blocks: %"PRIu64
"\n", aux_info
.len_blocks
);
523 printf(" Block groups: %d\n", aux_info
.groups
);
524 printf(" Reserved block group size: %d\n", info
.bg_desc_reserve_blocks
);
526 ext4_sparse_file
= sparse_file_new(info
.block_size
, info
.len
);
528 block_allocator_init();
532 if (reserve_inodes(0, 10) == EXT4_ALLOCATE_FAILED
)
533 error("failed to reserve first 10 inodes");
535 if (info
.feat_compat
& EXT4_FEATURE_COMPAT_HAS_JOURNAL
)
536 ext4_create_journal_inode();
538 if (info
.feat_compat
& EXT4_FEATURE_COMPAT_RESIZE_INODE
)
539 ext4_create_resize_inode();
542 // Windows needs only 'create an empty fs image' functionality
544 root_inode_num
= build_default_directory_structure(mountpoint
);
547 root_inode_num
= build_directory_structure(directory
, mountpoint
, 0,
548 fs_config_func
, verbose
, fixed_time
);
550 root_inode_num
= build_default_directory_structure(mountpoint
);
553 root_mode
= S_IRWXU
| S_IRGRP
| S_IXGRP
| S_IROTH
| S_IXOTH
;
554 inode_set_permissions(root_inode_num
, root_mode
, 0, 0, 0);
560 if (block_list_file
) {
561 size_t dirlen
= directory
? strlen(directory
) : 0;
562 struct block_allocation
* p
= get_saved_allocation_chain();
564 if (directory
&& strncmp(p
->filename
, directory
, dirlen
) == 0) {
565 // substitute mountpoint for the leading directory in the filename, in the output file
566 fprintf(block_list_file
, "%s%s", mountpoint
, p
->filename
+ dirlen
);
568 fprintf(block_list_file
, "%s", p
->filename
);
570 print_blocks(block_list_file
, p
);
571 struct block_allocation
* pn
= p
->next
;
577 printf("Created filesystem with %d/%d inodes and %d/%d blocks\n",
578 aux_info
.sb
->s_inodes_count
- aux_info
.sb
->s_free_inodes_count
,
579 aux_info
.sb
->s_inodes_count
,
580 aux_info
.sb
->s_blocks_count_lo
- aux_info
.sb
->s_free_blocks_count_lo
,
581 aux_info
.sb
->s_blocks_count_lo
);
583 if (wipe
&& WIPE_IS_SUPPORTED
) {
584 wipe_block_device(fd
, info
.len
);
587 write_ext4_image(fd
, gzip
, sparse
, crc
);
589 sparse_file_destroy(ext4_sparse_file
);
590 ext4_sparse_file
= NULL
;