Support tabs as seaprators when parsing fs config
[project/make_ext4fs.git] / ext4_utils.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 #include "ext4_utils.h"
18 #include "uuid.h"
19 #include "allocate.h"
20 #include "indirect.h"
21 #include "extent.h"
22
23 #include <sparse/sparse.h>
24
25 #include <fcntl.h>
26 #include <inttypes.h>
27 #include <sys/stat.h>
28 #include <sys/types.h>
29 #include <stddef.h>
30 #include <string.h>
31
32 #ifdef USE_MINGW
33 #include <winsock2.h>
34 #else
35 #include <arpa/inet.h>
36 #include <sys/ioctl.h>
37 #endif
38
39 #if defined(__linux__)
40 #include <linux/fs.h>
41 #elif defined(__APPLE__) && defined(__MACH__)
42 #include <sys/disk.h>
43 #endif
44
45 int force = 0;
46 struct fs_info info;
47 struct fs_aux_info aux_info;
48 struct sparse_file *ext4_sparse_file;
49
50 jmp_buf setjmp_env;
51
52 /* returns 1 if a is a power of b */
53 static int is_power_of(int a, int b)
54 {
55         while (a > b) {
56                 if (a % b)
57                         return 0;
58                 a /= b;
59         }
60
61         return (a == b) ? 1 : 0;
62 }
63
64 int bitmap_get_bit(u8 *bitmap, u32 bit)
65 {
66         if (bitmap[bit / 8] & (1 << (bit % 8)))
67                 return 1;
68
69         return 0;
70 }
71
72 void bitmap_clear_bit(u8 *bitmap, u32 bit)
73 {
74         bitmap[bit / 8] &= ~(1 << (bit % 8));
75
76         return;
77 }
78
79 /* Returns 1 if the bg contains a backup superblock.  On filesystems with
80    the sparse_super feature, only block groups 0, 1, and powers of 3, 5,
81    and 7 have backup superblocks.  Otherwise, all block groups have backup
82    superblocks */
83 int ext4_bg_has_super_block(int bg)
84 {
85         /* Without sparse_super, every block group has a superblock */
86         if (!(info.feat_ro_compat & EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER))
87                 return 1;
88
89         if (bg == 0 || bg == 1)
90                 return 1;
91
92         if (is_power_of(bg, 3) || is_power_of(bg, 5) || is_power_of(bg, 7))
93                 return 1;
94
95         return 0;
96 }
97
98 /* Function to read the primary superblock */
99 void read_sb(int fd, struct ext4_super_block *sb)
100 {
101         off64_t ret;
102
103         ret = lseek64(fd, 1024, SEEK_SET);
104         if (ret < 0)
105                 critical_error_errno("failed to seek to superblock");
106
107         ret = read(fd, sb, sizeof(*sb));
108         if (ret < 0)
109                 critical_error_errno("failed to read superblock");
110         if (ret != sizeof(*sb))
111                 critical_error("failed to read all of superblock");
112 }
113
114 /* Function to write a primary or backup superblock at a given offset */
115 void write_sb(int fd, unsigned long long offset, struct ext4_super_block *sb)
116 {
117         off64_t ret;
118
119         ret = lseek64(fd, offset, SEEK_SET);
120         if (ret < 0)
121                 critical_error_errno("failed to seek to superblock");
122
123         ret = write(fd, sb, sizeof(*sb));
124         if (ret < 0)
125                 critical_error_errno("failed to write superblock");
126         if (ret != sizeof(*sb))
127                 critical_error("failed to write all of superblock");
128 }
129
130 /* Write the filesystem image to a file */
131 void write_ext4_image(int fd, int gz, int sparse, int crc)
132 {
133         sparse_file_write(ext4_sparse_file, fd, gz, sparse, crc);
134 }
135
136 /* Compute the rest of the parameters of the filesystem from the basic info */
137 void ext4_create_fs_aux_info()
138 {
139         aux_info.first_data_block = (info.block_size > 1024) ? 0 : 1;
140         aux_info.len_blocks = info.len / info.block_size;
141         aux_info.inode_table_blocks = DIV_ROUND_UP(info.inodes_per_group * info.inode_size,
142                 info.block_size);
143         aux_info.groups = DIV_ROUND_UP(aux_info.len_blocks - aux_info.first_data_block,
144                 info.blocks_per_group);
145         aux_info.blocks_per_ind = info.block_size / sizeof(u32);
146         aux_info.blocks_per_dind = aux_info.blocks_per_ind * aux_info.blocks_per_ind;
147         aux_info.blocks_per_tind = aux_info.blocks_per_dind * aux_info.blocks_per_dind;
148
149         aux_info.bg_desc_blocks =
150                 DIV_ROUND_UP(aux_info.groups * sizeof(struct ext2_group_desc),
151                         info.block_size);
152
153         aux_info.default_i_flags = EXT4_NOATIME_FL;
154
155         u32 last_group_size = aux_info.len_blocks % info.blocks_per_group;
156         u32 last_header_size = 2 + aux_info.inode_table_blocks;
157         if (ext4_bg_has_super_block(aux_info.groups - 1))
158                 last_header_size += 1 + aux_info.bg_desc_blocks +
159                         info.bg_desc_reserve_blocks;
160         if (last_group_size > 0 && last_group_size < last_header_size) {
161                 aux_info.groups--;
162                 aux_info.len_blocks -= last_group_size;
163         }
164
165         aux_info.sb = calloc(info.block_size, 1);
166         /* Alloc an array to hold the pointers to the backup superblocks */
167         aux_info.backup_sb = calloc(aux_info.groups, sizeof(char *));
168
169         if (!aux_info.sb)
170                 critical_error_errno("calloc");
171
172         aux_info.bg_desc = calloc(info.block_size, aux_info.bg_desc_blocks);
173         if (!aux_info.bg_desc)
174                 critical_error_errno("calloc");
175         aux_info.xattrs = NULL;
176 }
177
178 void ext4_free_fs_aux_info()
179 {
180         unsigned int i;
181
182         for (i=0; i<aux_info.groups; i++) {
183                 if (aux_info.backup_sb[i])
184                         free(aux_info.backup_sb[i]);
185         }
186         free(aux_info.sb);
187         free(aux_info.bg_desc);
188 }
189
190 /* Fill in the superblock memory buffer based on the filesystem parameters */
191 void ext4_fill_in_sb()
192 {
193         unsigned int i;
194         struct ext4_super_block *sb = aux_info.sb;
195
196         sb->s_inodes_count = info.inodes_per_group * aux_info.groups;
197         sb->s_blocks_count_lo = aux_info.len_blocks;
198         sb->s_r_blocks_count_lo = 0;
199         sb->s_free_blocks_count_lo = 0;
200         sb->s_free_inodes_count = 0;
201         sb->s_first_data_block = aux_info.first_data_block;
202         sb->s_log_block_size = log_2(info.block_size / 1024);
203         sb->s_obso_log_frag_size = log_2(info.block_size / 1024);
204         sb->s_blocks_per_group = info.blocks_per_group;
205         sb->s_obso_frags_per_group = info.blocks_per_group;
206         sb->s_inodes_per_group = info.inodes_per_group;
207         sb->s_mtime = 0;
208         sb->s_wtime = 0;
209         sb->s_mnt_count = 0;
210         sb->s_max_mnt_count = 0xFFFF;
211         sb->s_magic = EXT4_SUPER_MAGIC;
212         sb->s_state = EXT4_VALID_FS;
213         sb->s_errors = EXT4_ERRORS_RO;
214         sb->s_minor_rev_level = 0;
215         sb->s_lastcheck = 0;
216         sb->s_checkinterval = 0;
217         sb->s_creator_os = EXT4_OS_LINUX;
218         sb->s_rev_level = EXT4_DYNAMIC_REV;
219         sb->s_def_resuid = EXT4_DEF_RESUID;
220         sb->s_def_resgid = EXT4_DEF_RESGID;
221
222         sb->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
223         sb->s_inode_size = info.inode_size;
224         sb->s_block_group_nr = 0;
225         sb->s_feature_compat = info.feat_compat;
226         sb->s_feature_incompat = info.feat_incompat;
227         sb->s_feature_ro_compat = info.feat_ro_compat;
228         generate_uuid("extandroid/make_ext4fs", info.label, sb->s_uuid);
229         memset(sb->s_volume_name, 0, sizeof(sb->s_volume_name));
230         strncpy(sb->s_volume_name, info.label, sizeof(sb->s_volume_name));
231         memset(sb->s_last_mounted, 0, sizeof(sb->s_last_mounted));
232         sb->s_algorithm_usage_bitmap = 0;
233
234         sb->s_reserved_gdt_blocks = info.bg_desc_reserve_blocks;
235         sb->s_prealloc_blocks = 0;
236         sb->s_prealloc_dir_blocks = 0;
237
238         //memcpy(sb->s_journal_uuid, sb->s_uuid, sizeof(sb->s_journal_uuid));
239         if (info.feat_compat & EXT4_FEATURE_COMPAT_HAS_JOURNAL)
240                 sb->s_journal_inum = EXT4_JOURNAL_INO;
241         sb->s_journal_dev = 0;
242         sb->s_last_orphan = 0;
243         sb->s_hash_seed[0] = 0; /* FIXME */
244         sb->s_def_hash_version = DX_HASH_TEA;
245         sb->s_reserved_char_pad = EXT4_JNL_BACKUP_BLOCKS;
246         sb->s_desc_size = sizeof(struct ext2_group_desc);
247         sb->s_default_mount_opts = 0; /* FIXME */
248         sb->s_first_meta_bg = 0;
249         sb->s_mkfs_time = 0;
250         //sb->s_jnl_blocks[17]; /* FIXME */
251
252         sb->s_blocks_count_hi = aux_info.len_blocks >> 32;
253         sb->s_r_blocks_count_hi = 0;
254         sb->s_free_blocks_count_hi = 0;
255         sb->s_min_extra_isize = sizeof(struct ext4_inode) -
256                 EXT4_GOOD_OLD_INODE_SIZE;
257         sb->s_want_extra_isize = sizeof(struct ext4_inode) -
258                 EXT4_GOOD_OLD_INODE_SIZE;
259         sb->s_flags = 2;
260         sb->s_raid_stride = 0;
261         sb->s_mmp_interval = 0;
262         sb->s_mmp_block = 0;
263         sb->s_raid_stripe_width = 0;
264         sb->s_log_groups_per_flex = 0;
265         sb->s_kbytes_written = 0;
266
267         for (i = 0; i < aux_info.groups; i++) {
268                 u64 group_start_block = aux_info.first_data_block + i *
269                         info.blocks_per_group;
270                 u32 header_size = 0;
271                 if (ext4_bg_has_super_block(i)) {
272                         if (i != 0) {
273                                 aux_info.backup_sb[i] = calloc(info.block_size, 1);
274                                 memcpy(aux_info.backup_sb[i], sb, info.block_size);
275                                 /* Update the block group nr of this backup superblock */
276                                 aux_info.backup_sb[i]->s_block_group_nr = i;
277                                 sparse_file_add_data(ext4_sparse_file, aux_info.backup_sb[i],
278                                                 info.block_size, group_start_block);
279                         }
280                         sparse_file_add_data(ext4_sparse_file, aux_info.bg_desc,
281                                 aux_info.bg_desc_blocks * info.block_size,
282                                 group_start_block + 1);
283                         header_size = 1 + aux_info.bg_desc_blocks + info.bg_desc_reserve_blocks;
284                 }
285
286                 aux_info.bg_desc[i].bg_block_bitmap = group_start_block + header_size;
287                 aux_info.bg_desc[i].bg_inode_bitmap = group_start_block + header_size + 1;
288                 aux_info.bg_desc[i].bg_inode_table = group_start_block + header_size + 2;
289
290                 aux_info.bg_desc[i].bg_free_blocks_count = sb->s_blocks_per_group;
291                 aux_info.bg_desc[i].bg_free_inodes_count = sb->s_inodes_per_group;
292                 aux_info.bg_desc[i].bg_used_dirs_count = 0;
293         }
294 }
295
296 void ext4_queue_sb(void)
297 {
298         /* The write_data* functions expect only block aligned calls.
299          * This is not an issue, except when we write out the super
300          * block on a system with a block size > 1K.  So, we need to
301          * deal with that here.
302          */
303         if (info.block_size > 1024) {
304                 u8 *buf = calloc(info.block_size, 1);
305                 memcpy(buf + 1024, (u8*)aux_info.sb, 1024);
306                 sparse_file_add_data(ext4_sparse_file, buf, info.block_size, 0);
307         } else {
308                 sparse_file_add_data(ext4_sparse_file, aux_info.sb, 1024, 1);
309         }
310 }
311
312 void ext4_parse_sb_info(struct ext4_super_block *sb)
313 {
314         if (sb->s_magic != EXT4_SUPER_MAGIC)
315                 error("superblock magic incorrect");
316
317         if ((sb->s_state & EXT4_VALID_FS) != EXT4_VALID_FS)
318                 error("filesystem state not valid");
319
320         ext4_parse_sb(sb, &info);
321
322         ext4_create_fs_aux_info();
323
324         memcpy(aux_info.sb, sb, sizeof(*sb));
325
326         if (aux_info.first_data_block != sb->s_first_data_block)
327                 critical_error("first data block does not match");
328 }
329
330 void ext4_create_resize_inode()
331 {
332         struct block_allocation *reserve_inode_alloc = create_allocation();
333         u32 reserve_inode_len = 0;
334         unsigned int i;
335
336         struct ext4_inode *inode = get_inode(EXT4_RESIZE_INO);
337         if (inode == NULL) {
338                 error("failed to get resize inode");
339                 return;
340         }
341
342         for (i = 0; i < aux_info.groups; i++) {
343                 if (ext4_bg_has_super_block(i)) {
344                         u64 group_start_block = aux_info.first_data_block + i *
345                                 info.blocks_per_group;
346                         u32 reserved_block_start = group_start_block + 1 +
347                                 aux_info.bg_desc_blocks;
348                         u32 reserved_block_len = info.bg_desc_reserve_blocks;
349                         append_region(reserve_inode_alloc, reserved_block_start,
350                                 reserved_block_len, i);
351                         reserve_inode_len += reserved_block_len;
352                 }
353         }
354
355         inode_attach_resize(inode, reserve_inode_alloc);
356
357         inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
358         inode->i_links_count = 1;
359
360         free_alloc(reserve_inode_alloc);
361 }
362
363 /* Allocate the blocks to hold a journal inode and connect them to the
364    reserved journal inode */
365 void ext4_create_journal_inode()
366 {
367         struct ext4_inode *inode = get_inode(EXT4_JOURNAL_INO);
368         if (inode == NULL) {
369                 error("failed to get journal inode");
370                 return;
371         }
372
373         u8 *journal_data = inode_allocate_data_extents(inode,
374                         info.journal_blocks * info.block_size,
375                         info.journal_blocks * info.block_size);
376         if (!journal_data) {
377                 error("failed to allocate extents for journal data");
378                 return;
379         }
380
381         inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
382         inode->i_links_count = 1;
383
384         journal_superblock_t *jsb = (journal_superblock_t *)journal_data;
385         jsb->s_header.h_magic = htonl(JBD2_MAGIC_NUMBER);
386         jsb->s_header.h_blocktype = htonl(JBD2_SUPERBLOCK_V2);
387         jsb->s_blocksize = htonl(info.block_size);
388         jsb->s_maxlen = htonl(info.journal_blocks);
389         jsb->s_nr_users = htonl(1);
390         jsb->s_first = htonl(1);
391         jsb->s_sequence = htonl(1);
392
393         memcpy(aux_info.sb->s_jnl_blocks, &inode->i_block, sizeof(inode->i_block));
394 }
395
396 /* Update the number of free blocks and inodes in the filesystem and in each
397    block group */
398 void ext4_update_free()
399 {
400         u32 i;
401
402         for (i = 0; i < aux_info.groups; i++) {
403                 u32 bg_free_blocks = get_free_blocks(i);
404                 u32 bg_free_inodes = get_free_inodes(i);
405                 u16 crc;
406
407                 aux_info.bg_desc[i].bg_free_blocks_count = bg_free_blocks;
408                 aux_info.sb->s_free_blocks_count_lo += bg_free_blocks;
409
410                 aux_info.bg_desc[i].bg_free_inodes_count = bg_free_inodes;
411                 aux_info.sb->s_free_inodes_count += bg_free_inodes;
412
413                 aux_info.bg_desc[i].bg_used_dirs_count += get_directories(i);
414
415                 aux_info.bg_desc[i].bg_flags = get_bg_flags(i);
416
417                 crc = ext4_crc16(~0, aux_info.sb->s_uuid, sizeof(aux_info.sb->s_uuid));
418                 crc = ext4_crc16(crc, &i, sizeof(i));
419                 crc = ext4_crc16(crc, &aux_info.bg_desc[i], offsetof(struct ext2_group_desc, bg_checksum));
420                 aux_info.bg_desc[i].bg_checksum = crc;
421         }
422 }
423
424 u64 get_block_device_size(int fd)
425 {
426         u64 size = 0;
427         int ret;
428
429 #if defined(__linux__)
430         ret = ioctl(fd, BLKGETSIZE64, &size);
431 #elif defined(__APPLE__) && defined(__MACH__)
432         ret = ioctl(fd, DKIOCGETBLOCKCOUNT, &size);
433 #else
434         close(fd);
435         return 0;
436 #endif
437
438         if (ret)
439                 return 0;
440
441         return size;
442 }
443
444 int is_block_device_fd(int fd)
445 {
446 #ifdef USE_MINGW
447         return 0;
448 #else
449         struct stat st;
450         int ret = fstat(fd, &st);
451         if (ret < 0)
452                 return 0;
453
454         return S_ISBLK(st.st_mode);
455 #endif
456 }
457
458 u64 get_file_size(int fd)
459 {
460         struct stat buf;
461         int ret;
462         u64 reserve_len = 0;
463         s64 computed_size;
464
465         ret = fstat(fd, &buf);
466         if (ret)
467                 return 0;
468
469         if (info.len < 0)
470                 reserve_len = -info.len;
471
472         if (S_ISREG(buf.st_mode))
473                 computed_size = buf.st_size - reserve_len;
474         else if (S_ISBLK(buf.st_mode))
475                 computed_size = get_block_device_size(fd) - reserve_len;
476         else
477                 computed_size = 0;
478
479         if (computed_size < 0) {
480                 warn("Computed filesystem size less than 0");
481                 computed_size = 0;
482         }
483
484         return computed_size;
485 }
486
487 u64 parse_num(const char *arg)
488 {
489         char *endptr;
490         u64 num = strtoull(arg, &endptr, 10);
491         if (*endptr == 'k' || *endptr == 'K')
492                 num *= 1024LL;
493         else if (*endptr == 'm' || *endptr == 'M')
494                 num *= 1024LL * 1024LL;
495         else if (*endptr == 'g' || *endptr == 'G')
496                 num *= 1024LL * 1024LL * 1024LL;
497
498         return num;
499 }
500
501 int read_ext(int fd, int verbose)
502 {
503         off64_t ret;
504         struct ext4_super_block sb;
505
506         read_sb(fd, &sb);
507
508         ext4_parse_sb_info(&sb);
509
510         ret = lseek64(fd, info.len, SEEK_SET);
511         if (ret < 0)
512                 critical_error_errno("failed to seek to end of input image");
513
514         ret = lseek64(fd, info.block_size * (aux_info.first_data_block + 1), SEEK_SET);
515         if (ret < 0)
516                 critical_error_errno("failed to seek to block group descriptors");
517
518         ret = read(fd, aux_info.bg_desc, info.block_size * aux_info.bg_desc_blocks);
519         if (ret < 0)
520                 critical_error_errno("failed to read block group descriptors");
521         if (ret != (int)info.block_size * (int)aux_info.bg_desc_blocks)
522                 critical_error("failed to read all of block group descriptors");
523
524         if (verbose) {
525                 printf("Found filesystem with parameters:\n");
526                 printf("    Size: %"PRIu64"\n", info.len);
527                 printf("    Block size: %d\n", info.block_size);
528                 printf("    Blocks per group: %d\n", info.blocks_per_group);
529                 printf("    Inodes per group: %d\n", info.inodes_per_group);
530                 printf("    Inode size: %d\n", info.inode_size);
531                 printf("    Label: %s\n", info.label);
532                 printf("    Blocks: %"PRIu64"\n", aux_info.len_blocks);
533                 printf("    Block groups: %d\n", aux_info.groups);
534                 printf("    Reserved block group size: %d\n", info.bg_desc_reserve_blocks);
535                 printf("    Used %d/%d inodes and %d/%d blocks\n",
536                         aux_info.sb->s_inodes_count - aux_info.sb->s_free_inodes_count,
537                         aux_info.sb->s_inodes_count,
538                         aux_info.sb->s_blocks_count_lo - aux_info.sb->s_free_blocks_count_lo,
539                         aux_info.sb->s_blocks_count_lo);
540         }
541
542         return 0;
543 }
544