1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2011 - 2012 Samsung Electronics
4 * EXT4 filesystem implementation in Uboot by
5 * Uma Shankar <uma.shankar@samsung.com>
6 * Manjunatha C Achar <a.manjunatha@samsung.com>
7 *
8 * ext4ls and ext4load : Based on ext2 ls load support in Uboot.
9 *
10 * (C) Copyright 2004
11 * esd gmbh <www.esd-electronics.com>
12 * Reinhard Arlt <reinhard.arlt@esd-electronics.com>
13 *
14 * based on code from grub2 fs/ext2.c and fs/fshelp.c by
15 * GRUB -- GRand Unified Bootloader
16 * Copyright (C) 2003, 2004 Free Software Foundation, Inc.
17 *
18 * ext4write : Based on generic ext4 protocol.
19 */
20
21 #include <blk.h>
22 #include <ext_common.h>
23 #include <ext4fs.h>
24 #include <log.h>
25 #include <malloc.h>
26 #include <memalign.h>
27 #include <part.h>
28 #include <stddef.h>
29 #include <linux/stat.h>
30 #include <linux/time.h>
31 #include <asm/byteorder.h>
32 #include "ext4_common.h"
33
34 struct ext2_data *ext4fs_root;
35 struct ext2fs_node *ext4fs_file;
36 __le32 *ext4fs_indir1_block;
37 int ext4fs_indir1_size;
38 int ext4fs_indir1_blkno = -1;
39 __le32 *ext4fs_indir2_block;
40 int ext4fs_indir2_size;
41 int ext4fs_indir2_blkno = -1;
42
43 __le32 *ext4fs_indir3_block;
44 int ext4fs_indir3_size;
45 int ext4fs_indir3_blkno = -1;
46 struct ext2_inode *g_parent_inode;
47 static int symlinknest;
48
49 #if defined(CONFIG_EXT4_WRITE)
ext4fs_get_group_descriptor(const struct ext_filesystem * fs,uint32_t bg_idx)50 struct ext2_block_group *ext4fs_get_group_descriptor
51 (const struct ext_filesystem *fs, uint32_t bg_idx)
52 {
53 return (struct ext2_block_group *)(fs->gdtable + (bg_idx * fs->gdsize));
54 }
55
ext4fs_sb_free_inodes_dec(struct ext2_sblock * sb)56 static inline void ext4fs_sb_free_inodes_dec(struct ext2_sblock *sb)
57 {
58 sb->free_inodes = cpu_to_le32(le32_to_cpu(sb->free_inodes) - 1);
59 }
60
ext4fs_sb_free_blocks_dec(struct ext2_sblock * sb)61 static inline void ext4fs_sb_free_blocks_dec(struct ext2_sblock *sb)
62 {
63 uint64_t free_blocks = le32_to_cpu(sb->free_blocks);
64 free_blocks += (uint64_t)le32_to_cpu(sb->free_blocks_high) << 32;
65 free_blocks--;
66
67 sb->free_blocks = cpu_to_le32(free_blocks & 0xffffffff);
68 sb->free_blocks_high = cpu_to_le16(free_blocks >> 32);
69 }
70
ext4fs_bg_free_inodes_dec(struct ext2_block_group * bg,const struct ext_filesystem * fs)71 static inline void ext4fs_bg_free_inodes_dec
72 (struct ext2_block_group *bg, const struct ext_filesystem *fs)
73 {
74 uint32_t free_inodes = le16_to_cpu(bg->free_inodes);
75 if (fs->gdsize == 64)
76 free_inodes += le16_to_cpu(bg->free_inodes_high) << 16;
77 free_inodes--;
78
79 bg->free_inodes = cpu_to_le16(free_inodes & 0xffff);
80 if (fs->gdsize == 64)
81 bg->free_inodes_high = cpu_to_le16(free_inodes >> 16);
82 }
83
ext4fs_bg_free_blocks_dec(struct ext2_block_group * bg,const struct ext_filesystem * fs)84 static inline void ext4fs_bg_free_blocks_dec
85 (struct ext2_block_group *bg, const struct ext_filesystem *fs)
86 {
87 uint32_t free_blocks = le16_to_cpu(bg->free_blocks);
88 if (fs->gdsize == 64)
89 free_blocks += le16_to_cpu(bg->free_blocks_high) << 16;
90 free_blocks--;
91
92 bg->free_blocks = cpu_to_le16(free_blocks & 0xffff);
93 if (fs->gdsize == 64)
94 bg->free_blocks_high = cpu_to_le16(free_blocks >> 16);
95 }
96
ext4fs_bg_itable_unused_dec(struct ext2_block_group * bg,const struct ext_filesystem * fs)97 static inline void ext4fs_bg_itable_unused_dec
98 (struct ext2_block_group *bg, const struct ext_filesystem *fs)
99 {
100 uint32_t free_inodes = le16_to_cpu(bg->bg_itable_unused);
101 if (fs->gdsize == 64)
102 free_inodes += le16_to_cpu(bg->bg_itable_unused_high) << 16;
103 free_inodes--;
104
105 bg->bg_itable_unused = cpu_to_le16(free_inodes & 0xffff);
106 if (fs->gdsize == 64)
107 bg->bg_itable_unused_high = cpu_to_le16(free_inodes >> 16);
108 }
109
ext4fs_sb_get_free_blocks(const struct ext2_sblock * sb)110 uint64_t ext4fs_sb_get_free_blocks(const struct ext2_sblock *sb)
111 {
112 uint64_t free_blocks = le32_to_cpu(sb->free_blocks);
113 free_blocks += (uint64_t)le32_to_cpu(sb->free_blocks_high) << 32;
114 return free_blocks;
115 }
116
ext4fs_sb_set_free_blocks(struct ext2_sblock * sb,uint64_t free_blocks)117 void ext4fs_sb_set_free_blocks(struct ext2_sblock *sb, uint64_t free_blocks)
118 {
119 sb->free_blocks = cpu_to_le32(free_blocks & 0xffffffff);
120 sb->free_blocks_high = cpu_to_le16(free_blocks >> 32);
121 }
122
ext4fs_bg_get_free_blocks(const struct ext2_block_group * bg,const struct ext_filesystem * fs)123 uint32_t ext4fs_bg_get_free_blocks(const struct ext2_block_group *bg,
124 const struct ext_filesystem *fs)
125 {
126 uint32_t free_blocks = le16_to_cpu(bg->free_blocks);
127 if (fs->gdsize == 64)
128 free_blocks += le16_to_cpu(bg->free_blocks_high) << 16;
129 return free_blocks;
130 }
131
132 static inline
ext4fs_bg_get_free_inodes(const struct ext2_block_group * bg,const struct ext_filesystem * fs)133 uint32_t ext4fs_bg_get_free_inodes(const struct ext2_block_group *bg,
134 const struct ext_filesystem *fs)
135 {
136 uint32_t free_inodes = le16_to_cpu(bg->free_inodes);
137 if (fs->gdsize == 64)
138 free_inodes += le16_to_cpu(bg->free_inodes_high) << 16;
139 return free_inodes;
140 }
141
ext4fs_bg_get_flags(const struct ext2_block_group * bg)142 static inline uint16_t ext4fs_bg_get_flags(const struct ext2_block_group *bg)
143 {
144 return le16_to_cpu(bg->bg_flags);
145 }
146
ext4fs_bg_set_flags(struct ext2_block_group * bg,uint16_t flags)147 static inline void ext4fs_bg_set_flags(struct ext2_block_group *bg,
148 uint16_t flags)
149 {
150 bg->bg_flags = cpu_to_le16(flags);
151 }
152
153 /* Block number of the block bitmap */
ext4fs_bg_get_block_id(const struct ext2_block_group * bg,const struct ext_filesystem * fs)154 uint64_t ext4fs_bg_get_block_id(const struct ext2_block_group *bg,
155 const struct ext_filesystem *fs)
156 {
157 uint64_t block_nr = le32_to_cpu(bg->block_id);
158 if (fs->gdsize == 64)
159 block_nr += (uint64_t)le32_to_cpu(bg->block_id_high) << 32;
160 return block_nr;
161 }
162
163 /* Block number of the inode bitmap */
ext4fs_bg_get_inode_id(const struct ext2_block_group * bg,const struct ext_filesystem * fs)164 uint64_t ext4fs_bg_get_inode_id(const struct ext2_block_group *bg,
165 const struct ext_filesystem *fs)
166 {
167 uint64_t block_nr = le32_to_cpu(bg->inode_id);
168 if (fs->gdsize == 64)
169 block_nr += (uint64_t)le32_to_cpu(bg->inode_id_high) << 32;
170 return block_nr;
171 }
172 #endif
173
174 /* Block number of the inode table */
ext4fs_bg_get_inode_table_id(const struct ext2_block_group * bg,const struct ext_filesystem * fs)175 uint64_t ext4fs_bg_get_inode_table_id(const struct ext2_block_group *bg,
176 const struct ext_filesystem *fs)
177 {
178 uint64_t block_nr = le32_to_cpu(bg->inode_table_id);
179 if (fs->gdsize == 64)
180 block_nr +=
181 (uint64_t)le32_to_cpu(bg->inode_table_id_high) << 32;
182 return block_nr;
183 }
184
185 #if defined(CONFIG_EXT4_WRITE)
ext4fs_div_roundup(uint32_t size,uint32_t n)186 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n)
187 {
188 uint32_t res = size / n;
189 if (res * n != size)
190 res++;
191
192 return res;
193 }
194
put_ext4(uint64_t off,const void * buf,uint32_t size)195 void put_ext4(uint64_t off, const void *buf, uint32_t size)
196 {
197 uint64_t startblock;
198 uint64_t remainder;
199 unsigned char *temp_ptr = NULL;
200 struct ext_filesystem *fs = get_fs();
201 int log2blksz;
202
203 if (!fs->dev_desc)
204 return;
205
206 ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz);
207
208 log2blksz = fs->dev_desc->log2blksz;
209 startblock = off >> log2blksz;
210 startblock += part_offset;
211 remainder = off & (uint64_t)(fs->dev_desc->blksz - 1);
212
213 if ((startblock + (size >> log2blksz)) >
214 (part_offset + fs->total_sect)) {
215 printf("part_offset is " LBAFU "\n", part_offset);
216 printf("total_sector is %llu\n", fs->total_sect);
217 printf("error: overflow occurs\n");
218 return;
219 }
220
221 if (remainder) {
222 blk_dread(fs->dev_desc, startblock, 1, sec_buf);
223 temp_ptr = sec_buf;
224 memcpy((temp_ptr + remainder), (unsigned char *)buf, size);
225 blk_dwrite(fs->dev_desc, startblock, 1, sec_buf);
226 } else {
227 if (size >> log2blksz != 0) {
228 blk_dwrite(fs->dev_desc, startblock, size >> log2blksz,
229 (unsigned long *)buf);
230 } else {
231 blk_dread(fs->dev_desc, startblock, 1, sec_buf);
232 temp_ptr = sec_buf;
233 memcpy(temp_ptr, buf, size);
234 blk_dwrite(fs->dev_desc, startblock, 1,
235 (unsigned long *)sec_buf);
236 }
237 }
238 }
239
_get_new_inode_no(unsigned char * buffer)240 static int _get_new_inode_no(unsigned char *buffer)
241 {
242 struct ext_filesystem *fs = get_fs();
243 unsigned char input;
244 int operand, status;
245 int count = 1;
246 int j = 0;
247
248 /* get the blocksize of the filesystem */
249 unsigned char *ptr = buffer;
250 while (*ptr == 255) {
251 ptr++;
252 count += 8;
253 if (count > le32_to_cpu(ext4fs_root->sblock.inodes_per_group))
254 return -1;
255 }
256
257 for (j = 0; j < fs->blksz; j++) {
258 input = *ptr;
259 int i = 0;
260 while (i <= 7) {
261 operand = 1 << i;
262 status = input & operand;
263 if (status) {
264 i++;
265 count++;
266 } else {
267 *ptr |= operand;
268 return count;
269 }
270 }
271 ptr = ptr + 1;
272 }
273
274 return -1;
275 }
276
_get_new_blk_no(unsigned char * buffer)277 static int _get_new_blk_no(unsigned char *buffer)
278 {
279 int operand;
280 int count = 0;
281 int i;
282 unsigned char *ptr = buffer;
283 struct ext_filesystem *fs = get_fs();
284
285 while (*ptr == 255) {
286 ptr++;
287 count += 8;
288 if (count == (fs->blksz * 8))
289 return -1;
290 }
291
292 if (fs->blksz == 1024)
293 count += 1;
294
295 for (i = 0; i <= 7; i++) {
296 operand = 1 << i;
297 if (*ptr & operand) {
298 count++;
299 } else {
300 *ptr |= operand;
301 return count;
302 }
303 }
304
305 return -1;
306 }
307
ext4fs_set_block_bmap(long int blockno,unsigned char * buffer,int index)308 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index)
309 {
310 int i, remainder, status;
311 unsigned char *ptr = buffer;
312 unsigned char operand;
313 i = blockno / 8;
314 remainder = blockno % 8;
315 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
316
317 i = i - (index * blocksize);
318 if (blocksize != 1024) {
319 ptr = ptr + i;
320 operand = 1 << remainder;
321 status = *ptr & operand;
322 if (status)
323 return -1;
324
325 *ptr = *ptr | operand;
326 return 0;
327 } else {
328 if (remainder == 0) {
329 ptr = ptr + i - 1;
330 operand = (1 << 7);
331 } else {
332 ptr = ptr + i;
333 operand = (1 << (remainder - 1));
334 }
335 status = *ptr & operand;
336 if (status)
337 return -1;
338
339 *ptr = *ptr | operand;
340 return 0;
341 }
342 }
343
ext4fs_reset_block_bmap(long int blockno,unsigned char * buffer,int index)344 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index)
345 {
346 int i, remainder, status;
347 unsigned char *ptr = buffer;
348 unsigned char operand;
349 i = blockno / 8;
350 remainder = blockno % 8;
351 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
352
353 i = i - (index * blocksize);
354 if (blocksize != 1024) {
355 ptr = ptr + i;
356 operand = (1 << remainder);
357 status = *ptr & operand;
358 if (status)
359 *ptr = *ptr & ~(operand);
360 } else {
361 if (remainder == 0) {
362 ptr = ptr + i - 1;
363 operand = (1 << 7);
364 } else {
365 ptr = ptr + i;
366 operand = (1 << (remainder - 1));
367 }
368 status = *ptr & operand;
369 if (status)
370 *ptr = *ptr & ~(operand);
371 }
372 }
373
ext4fs_set_inode_bmap(int inode_no,unsigned char * buffer,int index)374 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index)
375 {
376 int i, remainder, status;
377 unsigned char *ptr = buffer;
378 unsigned char operand;
379
380 inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group));
381 i = inode_no / 8;
382 remainder = inode_no % 8;
383 if (remainder == 0) {
384 ptr = ptr + i - 1;
385 operand = (1 << 7);
386 } else {
387 ptr = ptr + i;
388 operand = (1 << (remainder - 1));
389 }
390 status = *ptr & operand;
391 if (status)
392 return -1;
393
394 *ptr = *ptr | operand;
395
396 return 0;
397 }
398
ext4fs_reset_inode_bmap(int inode_no,unsigned char * buffer,int index)399 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index)
400 {
401 int i, remainder, status;
402 unsigned char *ptr = buffer;
403 unsigned char operand;
404
405 inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group));
406 i = inode_no / 8;
407 remainder = inode_no % 8;
408 if (remainder == 0) {
409 ptr = ptr + i - 1;
410 operand = (1 << 7);
411 } else {
412 ptr = ptr + i;
413 operand = (1 << (remainder - 1));
414 }
415 status = *ptr & operand;
416 if (status)
417 *ptr = *ptr & ~(operand);
418 }
419
ext4fs_checksum_update(uint32_t i)420 uint16_t ext4fs_checksum_update(uint32_t i)
421 {
422 struct ext2_block_group *desc;
423 struct ext_filesystem *fs = get_fs();
424 uint16_t crc = 0;
425 __le32 le32_i = cpu_to_le32(i);
426
427 desc = ext4fs_get_group_descriptor(fs, i);
428 if (le32_to_cpu(fs->sb->feature_ro_compat) & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
429 int offset = offsetof(struct ext2_block_group, bg_checksum);
430
431 crc = crc16(~0, (__u8 *)fs->sb->unique_id,
432 sizeof(fs->sb->unique_id));
433 crc = crc16(crc, (__u8 *)&le32_i, sizeof(le32_i));
434 crc = crc16(crc, (__u8 *)desc, offset);
435 offset += sizeof(desc->bg_checksum); /* skip checksum */
436 assert(offset == sizeof(*desc));
437 if (offset < fs->gdsize) {
438 crc = crc16(crc, (__u8 *)desc + offset,
439 fs->gdsize - offset);
440 }
441 }
442
443 return crc;
444 }
445
check_void_in_dentry(struct ext2_dirent * dir,char * filename)446 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename)
447 {
448 int dentry_length;
449 int sizeof_void_space;
450 int new_entry_byte_reqd;
451 short padding_factor = 0;
452
453 if (dir->namelen % 4 != 0)
454 padding_factor = 4 - (dir->namelen % 4);
455
456 dentry_length = sizeof(struct ext2_dirent) +
457 dir->namelen + padding_factor;
458 sizeof_void_space = le16_to_cpu(dir->direntlen) - dentry_length;
459 if (sizeof_void_space == 0)
460 return 0;
461
462 padding_factor = 0;
463 if (strlen(filename) % 4 != 0)
464 padding_factor = 4 - (strlen(filename) % 4);
465
466 new_entry_byte_reqd = strlen(filename) +
467 sizeof(struct ext2_dirent) + padding_factor;
468 if (sizeof_void_space >= new_entry_byte_reqd) {
469 dir->direntlen = cpu_to_le16(dentry_length);
470 return sizeof_void_space;
471 }
472
473 return 0;
474 }
475
ext4fs_update_parent_dentry(char * filename,int file_type)476 int ext4fs_update_parent_dentry(char *filename, int file_type)
477 {
478 unsigned int *zero_buffer = NULL;
479 char *root_first_block_buffer = NULL;
480 int blk_idx;
481 long int first_block_no_of_root = 0;
482 int totalbytes = 0;
483 unsigned int new_entry_byte_reqd;
484 int sizeof_void_space = 0;
485 int templength = 0;
486 int inodeno = -1;
487 int status;
488 struct ext_filesystem *fs = get_fs();
489 /* directory entry */
490 struct ext2_dirent *dir;
491 char *temp_dir = NULL;
492 uint32_t new_blk_no;
493 uint32_t new_size;
494 uint32_t new_blockcnt;
495 uint32_t directory_blocks;
496
497 zero_buffer = zalloc(fs->blksz);
498 if (!zero_buffer) {
499 printf("No Memory\n");
500 return -1;
501 }
502 root_first_block_buffer = zalloc(fs->blksz);
503 if (!root_first_block_buffer) {
504 free(zero_buffer);
505 printf("No Memory\n");
506 return -1;
507 }
508 new_entry_byte_reqd = ROUND(strlen(filename) +
509 sizeof(struct ext2_dirent), 4);
510 restart:
511 directory_blocks = le32_to_cpu(g_parent_inode->size) >>
512 LOG2_BLOCK_SIZE(ext4fs_root);
513 blk_idx = directory_blocks - 1;
514
515 restart_read:
516 /* read the block no allocated to a file */
517 first_block_no_of_root = read_allocated_block(g_parent_inode, blk_idx,
518 NULL);
519 if (first_block_no_of_root <= 0)
520 goto fail;
521
522 status = ext4fs_devread((lbaint_t)first_block_no_of_root
523 * fs->sect_perblk,
524 0, fs->blksz, root_first_block_buffer);
525 if (status == 0)
526 goto fail;
527
528 if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
529 goto fail;
530 dir = (struct ext2_dirent *)root_first_block_buffer;
531 totalbytes = 0;
532
533 while (le16_to_cpu(dir->direntlen) > 0) {
534 unsigned short used_len = ROUND(dir->namelen +
535 sizeof(struct ext2_dirent), 4);
536
537 /* last entry of block */
538 if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen)) {
539
540 /* check if new entry fits */
541 if ((used_len + new_entry_byte_reqd) <=
542 le16_to_cpu(dir->direntlen)) {
543 dir->direntlen = cpu_to_le16(used_len);
544 break;
545 } else {
546 if (blk_idx > 0) {
547 printf("Block full, trying previous\n");
548 blk_idx--;
549 goto restart_read;
550 }
551 printf("All blocks full: Allocate new\n");
552
553 if (le32_to_cpu(g_parent_inode->flags) &
554 EXT4_EXTENTS_FL) {
555 printf("Directory uses extents\n");
556 goto fail;
557 }
558 if (directory_blocks >= INDIRECT_BLOCKS) {
559 printf("Directory exceeds limit\n");
560 goto fail;
561 }
562 new_blk_no = ext4fs_get_new_blk_no();
563 if (new_blk_no == -1) {
564 printf("no block left to assign\n");
565 goto fail;
566 }
567 put_ext4((uint64_t)new_blk_no * fs->blksz, zero_buffer, fs->blksz);
568 g_parent_inode->b.blocks.
569 dir_blocks[directory_blocks] =
570 cpu_to_le32(new_blk_no);
571
572 new_size = le32_to_cpu(g_parent_inode->size);
573 new_size += fs->blksz;
574 g_parent_inode->size = cpu_to_le32(new_size);
575
576 new_blockcnt = le32_to_cpu(g_parent_inode->blockcnt);
577 new_blockcnt += fs->blksz >> LOG2_SECTOR_SIZE;
578 g_parent_inode->blockcnt = cpu_to_le32(new_blockcnt);
579
580 if (ext4fs_put_metadata
581 (root_first_block_buffer,
582 first_block_no_of_root))
583 goto fail;
584 goto restart;
585 }
586 }
587
588 templength = le16_to_cpu(dir->direntlen);
589 totalbytes = totalbytes + templength;
590 sizeof_void_space = check_void_in_dentry(dir, filename);
591 if (sizeof_void_space)
592 break;
593
594 dir = (struct ext2_dirent *)((char *)dir + templength);
595 }
596
597 /* make a pointer ready for creating next directory entry */
598 templength = le16_to_cpu(dir->direntlen);
599 totalbytes = totalbytes + templength;
600 dir = (struct ext2_dirent *)((char *)dir + templength);
601
602 /* get the next available inode number */
603 inodeno = ext4fs_get_new_inode_no();
604 if (inodeno == -1) {
605 printf("no inode left to assign\n");
606 goto fail;
607 }
608 dir->inode = cpu_to_le32(inodeno);
609 if (sizeof_void_space)
610 dir->direntlen = cpu_to_le16(sizeof_void_space);
611 else
612 dir->direntlen = cpu_to_le16(fs->blksz - totalbytes);
613
614 dir->namelen = strlen(filename);
615 dir->filetype = file_type;
616 temp_dir = (char *)dir;
617 temp_dir = temp_dir + sizeof(struct ext2_dirent);
618 memcpy(temp_dir, filename, strlen(filename));
619
620 /* update or write the 1st block of root inode */
621 if (ext4fs_put_metadata(root_first_block_buffer,
622 first_block_no_of_root))
623 goto fail;
624
625 fail:
626 free(zero_buffer);
627 free(root_first_block_buffer);
628
629 return inodeno;
630 }
631
search_dir(struct ext2_inode * parent_inode,char * dirname)632 static int search_dir(struct ext2_inode *parent_inode, char *dirname)
633 {
634 int status;
635 int inodeno = 0;
636 int offset;
637 int blk_idx;
638 long int blknr;
639 char *block_buffer = NULL;
640 struct ext2_dirent *dir = NULL;
641 struct ext_filesystem *fs = get_fs();
642 uint32_t directory_blocks;
643 char *direntname;
644
645 directory_blocks = le32_to_cpu(parent_inode->size) >>
646 LOG2_BLOCK_SIZE(ext4fs_root);
647
648 block_buffer = zalloc(fs->blksz);
649 if (!block_buffer)
650 goto fail;
651
652 /* get the block no allocated to a file */
653 for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) {
654 blknr = read_allocated_block(parent_inode, blk_idx, NULL);
655 if (blknr <= 0)
656 goto fail;
657
658 /* read the directory block */
659 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk,
660 0, fs->blksz, (char *)block_buffer);
661 if (status == 0)
662 goto fail;
663
664 offset = 0;
665 do {
666 if (offset & 3) {
667 printf("Badly aligned ext2_dirent\n");
668 break;
669 }
670
671 dir = (struct ext2_dirent *)(block_buffer + offset);
672 direntname = (char*)(dir) + sizeof(struct ext2_dirent);
673
674 int direntlen = le16_to_cpu(dir->direntlen);
675 if (direntlen < sizeof(struct ext2_dirent))
676 break;
677
678 if (dir->inode && (strlen(dirname) == dir->namelen) &&
679 (strncmp(dirname, direntname, dir->namelen) == 0)) {
680 inodeno = le32_to_cpu(dir->inode);
681 break;
682 }
683
684 offset += direntlen;
685
686 } while (offset < fs->blksz);
687
688 if (inodeno > 0) {
689 free(block_buffer);
690 return inodeno;
691 }
692 }
693
694 fail:
695 free(block_buffer);
696
697 return -1;
698 }
699
find_dir_depth(char * dirname)700 static int find_dir_depth(char *dirname)
701 {
702 char *token = strtok(dirname, "/");
703 int count = 0;
704 while (token != NULL) {
705 token = strtok(NULL, "/");
706 count++;
707 }
708 return count + 1 + 1;
709 /*
710 * for example for string /home/temp
711 * depth=home(1)+temp(1)+1 extra for NULL;
712 * so count is 4;
713 */
714 }
715
parse_path(char ** arr,char * dirname)716 static int parse_path(char **arr, char *dirname)
717 {
718 char *token = strtok(dirname, "/");
719 int i = 0;
720
721 /* add root */
722 arr[i] = zalloc(strlen("/") + 1);
723 if (!arr[i])
724 return -ENOMEM;
725 memcpy(arr[i++], "/", strlen("/"));
726
727 /* add each path entry after root */
728 while (token != NULL) {
729 arr[i] = zalloc(strlen(token) + 1);
730 if (!arr[i])
731 return -ENOMEM;
732 memcpy(arr[i++], token, strlen(token));
733 token = strtok(NULL, "/");
734 }
735 arr[i] = NULL;
736
737 return 0;
738 }
739
ext4fs_iget(int inode_no,struct ext2_inode * inode)740 int ext4fs_iget(int inode_no, struct ext2_inode *inode)
741 {
742 if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0)
743 return -1;
744
745 return 0;
746 }
747
748 /*
749 * Function: ext4fs_get_parent_inode_num
750 * Return Value: inode Number of the parent directory of file/Directory to be
751 * created
752 * dirname : Input parmater, input path name of the file/directory to be created
753 * dname : Output parameter, to be filled with the name of the directory
754 * extracted from dirname
755 */
ext4fs_get_parent_inode_num(const char * dirname,char * dname,int flags)756 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags)
757 {
758 int i;
759 int depth = 0;
760 int matched_inode_no;
761 int result_inode_no = -1;
762 char **ptr = NULL;
763 char *depth_dirname = NULL;
764 char *parse_dirname = NULL;
765 struct ext2_inode *parent_inode = NULL;
766 struct ext2_inode *first_inode = NULL;
767 struct ext2_inode temp_inode;
768
769 /* TODO: input validation make equivalent to linux */
770 depth_dirname = zalloc(strlen(dirname) + 1);
771 if (!depth_dirname)
772 return -ENOMEM;
773
774 memcpy(depth_dirname, dirname, strlen(dirname));
775 depth = find_dir_depth(depth_dirname);
776 parse_dirname = zalloc(strlen(dirname) + 1);
777 if (!parse_dirname)
778 goto fail;
779 memcpy(parse_dirname, dirname, strlen(dirname));
780
781 /* allocate memory for each directory level */
782 ptr = zalloc((depth) * sizeof(char *));
783 if (!ptr)
784 goto fail;
785 if (parse_path(ptr, parse_dirname))
786 goto fail;
787 parent_inode = zalloc(sizeof(struct ext2_inode));
788 if (!parent_inode)
789 goto fail;
790 first_inode = zalloc(sizeof(struct ext2_inode));
791 if (!first_inode)
792 goto fail;
793 memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode));
794 memcpy(first_inode, parent_inode, sizeof(struct ext2_inode));
795 if (flags & F_FILE)
796 result_inode_no = EXT2_ROOT_INO;
797 for (i = 1; i < depth; i++) {
798 matched_inode_no = search_dir(parent_inode, ptr[i]);
799 if (matched_inode_no == -1) {
800 if (ptr[i + 1] == NULL && i == 1) {
801 result_inode_no = EXT2_ROOT_INO;
802 goto end;
803 } else {
804 if (ptr[i + 1] == NULL)
805 break;
806 printf("Invalid path\n");
807 result_inode_no = -1;
808 goto fail;
809 }
810 } else {
811 if (ptr[i + 1] != NULL) {
812 memset(parent_inode, '\0',
813 sizeof(struct ext2_inode));
814 if (ext4fs_iget(matched_inode_no,
815 parent_inode)) {
816 result_inode_no = -1;
817 goto fail;
818 }
819 result_inode_no = matched_inode_no;
820 } else {
821 break;
822 }
823 }
824 }
825
826 end:
827 if (i == 1)
828 matched_inode_no = search_dir(first_inode, ptr[i]);
829 else
830 matched_inode_no = search_dir(parent_inode, ptr[i]);
831
832 if (matched_inode_no != -1) {
833 ext4fs_iget(matched_inode_no, &temp_inode);
834 if (le16_to_cpu(temp_inode.mode) & S_IFDIR) {
835 printf("It is a Directory\n");
836 result_inode_no = -1;
837 goto fail;
838 }
839 }
840
841 if (strlen(ptr[i]) > 256) {
842 result_inode_no = -1;
843 goto fail;
844 }
845 memcpy(dname, ptr[i], strlen(ptr[i]));
846
847 fail:
848 free(depth_dirname);
849 if (parse_dirname)
850 free(parse_dirname);
851 if (ptr) {
852 for (i = 0; i < depth; i++) {
853 if (!ptr[i])
854 break;
855 free(ptr[i]);
856 }
857 free(ptr);
858 }
859 if (parent_inode)
860 free(parent_inode);
861 if (first_inode)
862 free(first_inode);
863
864 return result_inode_no;
865 }
866
unlink_filename(char * filename,unsigned int blknr)867 static int unlink_filename(char *filename, unsigned int blknr)
868 {
869 int status;
870 int inodeno = 0;
871 int offset;
872 char *block_buffer = NULL;
873 struct ext2_dirent *dir = NULL;
874 struct ext2_dirent *previous_dir;
875 struct ext_filesystem *fs = get_fs();
876 int ret = -1;
877 char *direntname;
878
879 block_buffer = zalloc(fs->blksz);
880 if (!block_buffer)
881 return -ENOMEM;
882
883 /* read the directory block */
884 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
885 fs->blksz, block_buffer);
886 if (status == 0)
887 goto fail;
888
889 offset = 0;
890 do {
891 if (offset & 3) {
892 printf("Badly aligned ext2_dirent\n");
893 break;
894 }
895
896 previous_dir = dir;
897 dir = (struct ext2_dirent *)(block_buffer + offset);
898 direntname = (char *)(dir) + sizeof(struct ext2_dirent);
899
900 int direntlen = le16_to_cpu(dir->direntlen);
901 if (direntlen < sizeof(struct ext2_dirent))
902 break;
903
904 if (dir->inode && (strlen(filename) == dir->namelen) &&
905 (strncmp(direntname, filename, dir->namelen) == 0)) {
906 inodeno = le32_to_cpu(dir->inode);
907 break;
908 }
909
910 offset += direntlen;
911
912 } while (offset < fs->blksz);
913
914 if (inodeno > 0) {
915 printf("file found, deleting\n");
916 if (ext4fs_log_journal(block_buffer, blknr))
917 goto fail;
918
919 if (previous_dir) {
920 /* merge dir entry with predecessor */
921 uint16_t new_len;
922 new_len = le16_to_cpu(previous_dir->direntlen);
923 new_len += le16_to_cpu(dir->direntlen);
924 previous_dir->direntlen = cpu_to_le16(new_len);
925 } else {
926 /* invalidate dir entry */
927 dir->inode = 0;
928 }
929 if (ext4fs_put_metadata(block_buffer, blknr))
930 goto fail;
931 ret = inodeno;
932 }
933 fail:
934 free(block_buffer);
935
936 return ret;
937 }
938
ext4fs_filename_unlink(char * filename)939 int ext4fs_filename_unlink(char *filename)
940 {
941 int blk_idx;
942 long int blknr = -1;
943 int inodeno = -1;
944 uint32_t directory_blocks;
945
946 directory_blocks = le32_to_cpu(g_parent_inode->size) >>
947 LOG2_BLOCK_SIZE(ext4fs_root);
948
949 /* read the block no allocated to a file */
950 for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) {
951 blknr = read_allocated_block(g_parent_inode, blk_idx, NULL);
952 if (blknr <= 0)
953 break;
954 inodeno = unlink_filename(filename, blknr);
955 if (inodeno != -1)
956 return inodeno;
957 }
958
959 return -1;
960 }
961
ext4fs_get_new_blk_no(void)962 uint32_t ext4fs_get_new_blk_no(void)
963 {
964 short i;
965 short status;
966 int remainder;
967 unsigned int bg_idx;
968 static int prev_bg_bitmap_index = -1;
969 unsigned int blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
970 struct ext_filesystem *fs = get_fs();
971 char *journal_buffer = zalloc(fs->blksz);
972 char *zero_buffer = zalloc(fs->blksz);
973 if (!journal_buffer || !zero_buffer)
974 goto fail;
975
976 if (fs->first_pass_bbmap == 0) {
977 for (i = 0; i < fs->no_blkgrp; i++) {
978 struct ext2_block_group *bgd = NULL;
979 bgd = ext4fs_get_group_descriptor(fs, i);
980 if (ext4fs_bg_get_free_blocks(bgd, fs)) {
981 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
982 uint64_t b_bitmap_blk =
983 ext4fs_bg_get_block_id(bgd, fs);
984 if (bg_flags & EXT4_BG_BLOCK_UNINIT) {
985 memcpy(fs->blk_bmaps[i], zero_buffer,
986 fs->blksz);
987 put_ext4(b_bitmap_blk * fs->blksz,
988 fs->blk_bmaps[i], fs->blksz);
989 bg_flags &= ~EXT4_BG_BLOCK_UNINIT;
990 ext4fs_bg_set_flags(bgd, bg_flags);
991 }
992 fs->curr_blkno =
993 _get_new_blk_no(fs->blk_bmaps[i]);
994 if (fs->curr_blkno == -1)
995 /* block bitmap is completely filled */
996 continue;
997 fs->curr_blkno = fs->curr_blkno +
998 (i * fs->blksz * 8);
999 fs->first_pass_bbmap++;
1000 ext4fs_bg_free_blocks_dec(bgd, fs);
1001 ext4fs_sb_free_blocks_dec(fs->sb);
1002 status = ext4fs_devread(b_bitmap_blk *
1003 fs->sect_perblk,
1004 0, fs->blksz,
1005 journal_buffer);
1006 if (status == 0)
1007 goto fail;
1008 if (ext4fs_log_journal(journal_buffer,
1009 b_bitmap_blk))
1010 goto fail;
1011 goto success;
1012 } else {
1013 debug("no space left on block group %d\n", i);
1014 }
1015 }
1016
1017 goto fail;
1018 } else {
1019 fs->curr_blkno++;
1020 restart:
1021 /* get the blockbitmap index respective to blockno */
1022 bg_idx = fs->curr_blkno / blk_per_grp;
1023 if (fs->blksz == 1024) {
1024 remainder = fs->curr_blkno % blk_per_grp;
1025 if (!remainder)
1026 bg_idx--;
1027 }
1028
1029 /*
1030 * To skip completely filled block group bitmaps
1031 * Optimize the block allocation
1032 */
1033 if (bg_idx >= fs->no_blkgrp)
1034 goto fail;
1035
1036 struct ext2_block_group *bgd = NULL;
1037 bgd = ext4fs_get_group_descriptor(fs, bg_idx);
1038 if (ext4fs_bg_get_free_blocks(bgd, fs) == 0) {
1039 debug("block group %u is full. Skipping\n", bg_idx);
1040 fs->curr_blkno = (bg_idx + 1) * blk_per_grp;
1041 if (fs->blksz == 1024)
1042 fs->curr_blkno += 1;
1043 goto restart;
1044 }
1045
1046 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
1047 uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
1048 if (bg_flags & EXT4_BG_BLOCK_UNINIT) {
1049 memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
1050 put_ext4(b_bitmap_blk * fs->blksz,
1051 zero_buffer, fs->blksz);
1052 bg_flags &= ~EXT4_BG_BLOCK_UNINIT;
1053 ext4fs_bg_set_flags(bgd, bg_flags);
1054 }
1055
1056 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
1057 bg_idx) != 0) {
1058 debug("going for restart for the block no %ld %u\n",
1059 fs->curr_blkno, bg_idx);
1060 fs->curr_blkno++;
1061 goto restart;
1062 }
1063
1064 /* journal backup */
1065 if (prev_bg_bitmap_index != bg_idx) {
1066 status = ext4fs_devread(b_bitmap_blk * fs->sect_perblk,
1067 0, fs->blksz, journal_buffer);
1068 if (status == 0)
1069 goto fail;
1070 if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
1071 goto fail;
1072
1073 prev_bg_bitmap_index = bg_idx;
1074 }
1075 ext4fs_bg_free_blocks_dec(bgd, fs);
1076 ext4fs_sb_free_blocks_dec(fs->sb);
1077 goto success;
1078 }
1079 success:
1080 free(journal_buffer);
1081 free(zero_buffer);
1082
1083 return fs->curr_blkno;
1084 fail:
1085 free(journal_buffer);
1086 free(zero_buffer);
1087
1088 return -1;
1089 }
1090
ext4fs_get_new_inode_no(void)1091 int ext4fs_get_new_inode_no(void)
1092 {
1093 short i;
1094 short status;
1095 unsigned int ibmap_idx;
1096 static int prev_inode_bitmap_index = -1;
1097 unsigned int inodes_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
1098 struct ext_filesystem *fs = get_fs();
1099 char *journal_buffer = zalloc(fs->blksz);
1100 char *zero_buffer = zalloc(fs->blksz);
1101 if (!journal_buffer || !zero_buffer)
1102 goto fail;
1103 int has_gdt_chksum = le32_to_cpu(fs->sb->feature_ro_compat) &
1104 EXT4_FEATURE_RO_COMPAT_GDT_CSUM ? 1 : 0;
1105
1106 if (fs->first_pass_ibmap == 0) {
1107 for (i = 0; i < fs->no_blkgrp; i++) {
1108 uint32_t free_inodes;
1109 struct ext2_block_group *bgd = NULL;
1110 bgd = ext4fs_get_group_descriptor(fs, i);
1111 free_inodes = ext4fs_bg_get_free_inodes(bgd, fs);
1112 if (free_inodes) {
1113 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
1114 uint64_t i_bitmap_blk =
1115 ext4fs_bg_get_inode_id(bgd, fs);
1116 if (has_gdt_chksum)
1117 bgd->bg_itable_unused = free_inodes;
1118 if (bg_flags & EXT4_BG_INODE_UNINIT) {
1119 put_ext4(i_bitmap_blk * fs->blksz,
1120 zero_buffer, fs->blksz);
1121 bg_flags &= ~EXT4_BG_INODE_UNINIT;
1122 ext4fs_bg_set_flags(bgd, bg_flags);
1123 memcpy(fs->inode_bmaps[i],
1124 zero_buffer, fs->blksz);
1125 }
1126 fs->curr_inode_no =
1127 _get_new_inode_no(fs->inode_bmaps[i]);
1128 if (fs->curr_inode_no == -1)
1129 /* inode bitmap is completely filled */
1130 continue;
1131 fs->curr_inode_no = fs->curr_inode_no +
1132 (i * inodes_per_grp);
1133 fs->first_pass_ibmap++;
1134 ext4fs_bg_free_inodes_dec(bgd, fs);
1135 if (has_gdt_chksum)
1136 ext4fs_bg_itable_unused_dec(bgd, fs);
1137 ext4fs_sb_free_inodes_dec(fs->sb);
1138 status = ext4fs_devread(i_bitmap_blk *
1139 fs->sect_perblk,
1140 0, fs->blksz,
1141 journal_buffer);
1142 if (status == 0)
1143 goto fail;
1144 if (ext4fs_log_journal(journal_buffer,
1145 i_bitmap_blk))
1146 goto fail;
1147 goto success;
1148 } else
1149 debug("no inode left on block group %d\n", i);
1150 }
1151 goto fail;
1152 } else {
1153 restart:
1154 fs->curr_inode_no++;
1155 /* get the blockbitmap index respective to blockno */
1156 ibmap_idx = fs->curr_inode_no / inodes_per_grp;
1157 struct ext2_block_group *bgd =
1158 ext4fs_get_group_descriptor(fs, ibmap_idx);
1159 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
1160 uint64_t i_bitmap_blk = ext4fs_bg_get_inode_id(bgd, fs);
1161
1162 if (bg_flags & EXT4_BG_INODE_UNINIT) {
1163 put_ext4(i_bitmap_blk * fs->blksz,
1164 zero_buffer, fs->blksz);
1165 bg_flags &= ~EXT4_BG_INODE_UNINIT;
1166 ext4fs_bg_set_flags(bgd, bg_flags);
1167 memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
1168 fs->blksz);
1169 }
1170
1171 if (ext4fs_set_inode_bmap(fs->curr_inode_no,
1172 fs->inode_bmaps[ibmap_idx],
1173 ibmap_idx) != 0) {
1174 debug("going for restart for the block no %d %u\n",
1175 fs->curr_inode_no, ibmap_idx);
1176 goto restart;
1177 }
1178
1179 /* journal backup */
1180 if (prev_inode_bitmap_index != ibmap_idx) {
1181 status = ext4fs_devread(i_bitmap_blk * fs->sect_perblk,
1182 0, fs->blksz, journal_buffer);
1183 if (status == 0)
1184 goto fail;
1185 if (ext4fs_log_journal(journal_buffer,
1186 le32_to_cpu(bgd->inode_id)))
1187 goto fail;
1188 prev_inode_bitmap_index = ibmap_idx;
1189 }
1190 ext4fs_bg_free_inodes_dec(bgd, fs);
1191 if (has_gdt_chksum)
1192 bgd->bg_itable_unused = bgd->free_inodes;
1193 ext4fs_sb_free_inodes_dec(fs->sb);
1194 goto success;
1195 }
1196
1197 success:
1198 free(journal_buffer);
1199 free(zero_buffer);
1200
1201 return fs->curr_inode_no;
1202 fail:
1203 free(journal_buffer);
1204 free(zero_buffer);
1205
1206 return -1;
1207
1208 }
1209
alloc_single_indirect_block(struct ext2_inode * file_inode,unsigned int * total_remaining_blocks,unsigned int * no_blks_reqd)1210 static void alloc_single_indirect_block(struct ext2_inode *file_inode,
1211 unsigned int *total_remaining_blocks,
1212 unsigned int *no_blks_reqd)
1213 {
1214 short i;
1215 short status;
1216 long int actual_block_no;
1217 long int si_blockno;
1218 /* si :single indirect */
1219 __le32 *si_buffer = NULL;
1220 __le32 *si_start_addr = NULL;
1221 struct ext_filesystem *fs = get_fs();
1222
1223 if (*total_remaining_blocks != 0) {
1224 si_buffer = zalloc(fs->blksz);
1225 if (!si_buffer) {
1226 printf("No Memory\n");
1227 return;
1228 }
1229 si_start_addr = si_buffer;
1230 si_blockno = ext4fs_get_new_blk_no();
1231 if (si_blockno == -1) {
1232 printf("no block left to assign\n");
1233 goto fail;
1234 }
1235 (*no_blks_reqd)++;
1236 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
1237
1238 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk,
1239 0, fs->blksz, (char *)si_buffer);
1240 memset(si_buffer, '\0', fs->blksz);
1241 if (status == 0)
1242 goto fail;
1243
1244 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1245 actual_block_no = ext4fs_get_new_blk_no();
1246 if (actual_block_no == -1) {
1247 printf("no block left to assign\n");
1248 goto fail;
1249 }
1250 *si_buffer = cpu_to_le32(actual_block_no);
1251 debug("SIAB %u: %u\n", *si_buffer,
1252 *total_remaining_blocks);
1253
1254 si_buffer++;
1255 (*total_remaining_blocks)--;
1256 if (*total_remaining_blocks == 0)
1257 break;
1258 }
1259
1260 /* write the block to disk */
1261 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)),
1262 si_start_addr, fs->blksz);
1263 file_inode->b.blocks.indir_block = cpu_to_le32(si_blockno);
1264 }
1265 fail:
1266 free(si_start_addr);
1267 }
1268
alloc_double_indirect_block(struct ext2_inode * file_inode,unsigned int * total_remaining_blocks,unsigned int * no_blks_reqd)1269 static void alloc_double_indirect_block(struct ext2_inode *file_inode,
1270 unsigned int *total_remaining_blocks,
1271 unsigned int *no_blks_reqd)
1272 {
1273 short i;
1274 short j;
1275 short status;
1276 long int actual_block_no;
1277 /* di:double indirect */
1278 long int di_blockno_parent;
1279 long int di_blockno_child;
1280 __le32 *di_parent_buffer = NULL;
1281 __le32 *di_child_buff = NULL;
1282 __le32 *di_block_start_addr = NULL;
1283 __le32 *di_child_buff_start = NULL;
1284 struct ext_filesystem *fs = get_fs();
1285
1286 if (*total_remaining_blocks != 0) {
1287 /* double indirect parent block connecting to inode */
1288 di_blockno_parent = ext4fs_get_new_blk_no();
1289 if (di_blockno_parent == -1) {
1290 printf("no block left to assign\n");
1291 goto fail;
1292 }
1293 di_parent_buffer = zalloc(fs->blksz);
1294 if (!di_parent_buffer)
1295 goto fail;
1296
1297 di_block_start_addr = di_parent_buffer;
1298 (*no_blks_reqd)++;
1299 debug("DIPB %ld: %u\n", di_blockno_parent,
1300 *total_remaining_blocks);
1301
1302 status = ext4fs_devread((lbaint_t)di_blockno_parent *
1303 fs->sect_perblk, 0,
1304 fs->blksz, (char *)di_parent_buffer);
1305
1306 if (!status) {
1307 printf("%s: Device read error!\n", __func__);
1308 goto fail;
1309 }
1310 memset(di_parent_buffer, '\0', fs->blksz);
1311
1312 /*
1313 * start:for each double indirect parent
1314 * block create one more block
1315 */
1316 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1317 di_blockno_child = ext4fs_get_new_blk_no();
1318 if (di_blockno_child == -1) {
1319 printf("no block left to assign\n");
1320 goto fail;
1321 }
1322 di_child_buff = zalloc(fs->blksz);
1323 if (!di_child_buff)
1324 goto fail;
1325
1326 di_child_buff_start = di_child_buff;
1327 *di_parent_buffer = cpu_to_le32(di_blockno_child);
1328 di_parent_buffer++;
1329 (*no_blks_reqd)++;
1330 debug("DICB %ld: %u\n", di_blockno_child,
1331 *total_remaining_blocks);
1332
1333 status = ext4fs_devread((lbaint_t)di_blockno_child *
1334 fs->sect_perblk, 0,
1335 fs->blksz,
1336 (char *)di_child_buff);
1337
1338 if (!status) {
1339 printf("%s: Device read error!\n", __func__);
1340 goto fail;
1341 }
1342 memset(di_child_buff, '\0', fs->blksz);
1343 /* filling of actual datablocks for each child */
1344 for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1345 actual_block_no = ext4fs_get_new_blk_no();
1346 if (actual_block_no == -1) {
1347 printf("no block left to assign\n");
1348 goto fail;
1349 }
1350 *di_child_buff = cpu_to_le32(actual_block_no);
1351 debug("DIAB %ld: %u\n", actual_block_no,
1352 *total_remaining_blocks);
1353
1354 di_child_buff++;
1355 (*total_remaining_blocks)--;
1356 if (*total_remaining_blocks == 0)
1357 break;
1358 }
1359 /* write the block table */
1360 put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)),
1361 di_child_buff_start, fs->blksz);
1362 free(di_child_buff_start);
1363 di_child_buff_start = NULL;
1364
1365 if (*total_remaining_blocks == 0)
1366 break;
1367 }
1368 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)),
1369 di_block_start_addr, fs->blksz);
1370 file_inode->b.blocks.double_indir_block = cpu_to_le32(di_blockno_parent);
1371 }
1372 fail:
1373 free(di_block_start_addr);
1374 }
1375
alloc_triple_indirect_block(struct ext2_inode * file_inode,unsigned int * total_remaining_blocks,unsigned int * no_blks_reqd)1376 static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
1377 unsigned int *total_remaining_blocks,
1378 unsigned int *no_blks_reqd)
1379 {
1380 short i;
1381 short j;
1382 short k;
1383 long int actual_block_no;
1384 /* ti: Triple Indirect */
1385 long int ti_gp_blockno;
1386 long int ti_parent_blockno;
1387 long int ti_child_blockno;
1388 __le32 *ti_gp_buff = NULL;
1389 __le32 *ti_parent_buff = NULL;
1390 __le32 *ti_child_buff = NULL;
1391 __le32 *ti_gp_buff_start_addr = NULL;
1392 __le32 *ti_pbuff_start_addr = NULL;
1393 __le32 *ti_cbuff_start_addr = NULL;
1394 struct ext_filesystem *fs = get_fs();
1395 if (*total_remaining_blocks != 0) {
1396 /* triple indirect grand parent block connecting to inode */
1397 ti_gp_blockno = ext4fs_get_new_blk_no();
1398 if (ti_gp_blockno == -1) {
1399 printf("no block left to assign\n");
1400 return;
1401 }
1402 ti_gp_buff = zalloc(fs->blksz);
1403 if (!ti_gp_buff)
1404 return;
1405
1406 ti_gp_buff_start_addr = ti_gp_buff;
1407 (*no_blks_reqd)++;
1408 debug("TIGPB %ld: %u\n", ti_gp_blockno,
1409 *total_remaining_blocks);
1410
1411 /* for each 4 byte grand parent entry create one more block */
1412 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1413 ti_parent_blockno = ext4fs_get_new_blk_no();
1414 if (ti_parent_blockno == -1) {
1415 printf("no block left to assign\n");
1416 goto fail;
1417 }
1418 ti_parent_buff = zalloc(fs->blksz);
1419 if (!ti_parent_buff)
1420 goto fail;
1421
1422 ti_pbuff_start_addr = ti_parent_buff;
1423 *ti_gp_buff = cpu_to_le32(ti_parent_blockno);
1424 ti_gp_buff++;
1425 (*no_blks_reqd)++;
1426 debug("TIPB %ld: %u\n", ti_parent_blockno,
1427 *total_remaining_blocks);
1428
1429 /* for each 4 byte entry parent create one more block */
1430 for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1431 ti_child_blockno = ext4fs_get_new_blk_no();
1432 if (ti_child_blockno == -1) {
1433 printf("no block left assign\n");
1434 goto fail1;
1435 }
1436 ti_child_buff = zalloc(fs->blksz);
1437 if (!ti_child_buff)
1438 goto fail1;
1439
1440 ti_cbuff_start_addr = ti_child_buff;
1441 *ti_parent_buff = cpu_to_le32(ti_child_blockno);
1442 ti_parent_buff++;
1443 (*no_blks_reqd)++;
1444 debug("TICB %ld: %u\n", ti_parent_blockno,
1445 *total_remaining_blocks);
1446
1447 /* fill actual datablocks for each child */
1448 for (k = 0; k < (fs->blksz / sizeof(int));
1449 k++) {
1450 actual_block_no =
1451 ext4fs_get_new_blk_no();
1452 if (actual_block_no == -1) {
1453 printf("no block left\n");
1454 free(ti_cbuff_start_addr);
1455 goto fail1;
1456 }
1457 *ti_child_buff = cpu_to_le32(actual_block_no);
1458 debug("TIAB %ld: %u\n", actual_block_no,
1459 *total_remaining_blocks);
1460
1461 ti_child_buff++;
1462 (*total_remaining_blocks)--;
1463 if (*total_remaining_blocks == 0)
1464 break;
1465 }
1466 /* write the child block */
1467 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno *
1468 (uint64_t)fs->blksz)),
1469 ti_cbuff_start_addr, fs->blksz);
1470 free(ti_cbuff_start_addr);
1471
1472 if (*total_remaining_blocks == 0)
1473 break;
1474 }
1475 /* write the parent block */
1476 put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)),
1477 ti_pbuff_start_addr, fs->blksz);
1478 free(ti_pbuff_start_addr);
1479
1480 if (*total_remaining_blocks == 0)
1481 break;
1482 }
1483 /* write the grand parent block */
1484 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)),
1485 ti_gp_buff_start_addr, fs->blksz);
1486 file_inode->b.blocks.triple_indir_block = cpu_to_le32(ti_gp_blockno);
1487 free(ti_gp_buff_start_addr);
1488 return;
1489 }
1490 fail1:
1491 free(ti_pbuff_start_addr);
1492 fail:
1493 free(ti_gp_buff_start_addr);
1494 }
1495
ext4fs_allocate_blocks(struct ext2_inode * file_inode,unsigned int total_remaining_blocks,unsigned int * total_no_of_block)1496 void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
1497 unsigned int total_remaining_blocks,
1498 unsigned int *total_no_of_block)
1499 {
1500 short i;
1501 long int direct_blockno;
1502 unsigned int no_blks_reqd = 0;
1503
1504 /* allocation of direct blocks */
1505 for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) {
1506 direct_blockno = ext4fs_get_new_blk_no();
1507 if (direct_blockno == -1) {
1508 printf("no block left to assign\n");
1509 return;
1510 }
1511 file_inode->b.blocks.dir_blocks[i] = cpu_to_le32(direct_blockno);
1512 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
1513
1514 total_remaining_blocks--;
1515 }
1516
1517 alloc_single_indirect_block(file_inode, &total_remaining_blocks,
1518 &no_blks_reqd);
1519 alloc_double_indirect_block(file_inode, &total_remaining_blocks,
1520 &no_blks_reqd);
1521 alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
1522 &no_blks_reqd);
1523 *total_no_of_block += no_blks_reqd;
1524 }
1525
1526 #endif
1527
ext4fs_get_extent_block(struct ext2_data * data,struct ext_block_cache * cache,struct ext4_extent_header * ext_block,uint32_t fileblock,int log2_blksz)1528 static struct ext4_extent_header *ext4fs_get_extent_block
1529 (struct ext2_data *data, struct ext_block_cache *cache,
1530 struct ext4_extent_header *ext_block,
1531 uint32_t fileblock, int log2_blksz)
1532 {
1533 struct ext4_extent_idx *index;
1534 unsigned long long block;
1535 int blksz = EXT2_BLOCK_SIZE(data);
1536 int i;
1537
1538 while (1) {
1539 index = (struct ext4_extent_idx *)(ext_block + 1);
1540
1541 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
1542 return NULL;
1543
1544 if (ext_block->eh_depth == 0)
1545 return ext_block;
1546 i = -1;
1547 do {
1548 i++;
1549 if (i >= le16_to_cpu(ext_block->eh_entries))
1550 break;
1551 } while (fileblock >= le32_to_cpu(index[i].ei_block));
1552
1553 /*
1554 * If first logical block number is higher than requested fileblock,
1555 * it is a sparse file. This is handled on upper layer.
1556 */
1557 if (i > 0)
1558 i--;
1559
1560 block = le16_to_cpu(index[i].ei_leaf_hi);
1561 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
1562 block <<= log2_blksz;
1563 if (!ext_cache_read(cache, (lbaint_t)block, blksz))
1564 return NULL;
1565 ext_block = (struct ext4_extent_header *)cache->buf;
1566 }
1567 }
1568
ext4fs_blockgroup(struct ext2_data * data,int group,struct ext2_block_group * blkgrp)1569 static int ext4fs_blockgroup
1570 (struct ext2_data *data, int group, struct ext2_block_group *blkgrp)
1571 {
1572 long int blkno;
1573 unsigned int blkoff, desc_per_blk;
1574 int log2blksz = get_fs()->dev_desc->log2blksz;
1575 int desc_size = get_fs()->gdsize;
1576
1577 if (desc_size == 0)
1578 return 0;
1579 desc_per_blk = EXT2_BLOCK_SIZE(data) / desc_size;
1580
1581 if (desc_per_blk == 0)
1582 return 0;
1583 blkno = le32_to_cpu(data->sblock.first_data_block) + 1 +
1584 group / desc_per_blk;
1585 blkoff = (group % desc_per_blk) * desc_size;
1586
1587 debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n",
1588 group, blkno, blkoff);
1589
1590 return ext4fs_devread((lbaint_t)blkno <<
1591 (LOG2_BLOCK_SIZE(data) - log2blksz),
1592 blkoff, desc_size, (char *)blkgrp);
1593 }
1594
ext4fs_read_inode(struct ext2_data * data,int ino,struct ext2_inode * inode)1595 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
1596 {
1597 struct ext2_block_group *blkgrp;
1598 struct ext2_sblock *sblock = &data->sblock;
1599 struct ext_filesystem *fs = get_fs();
1600 int log2blksz = get_fs()->dev_desc->log2blksz;
1601 int inodes_per_block, status;
1602 long int blkno;
1603 unsigned int blkoff;
1604
1605 /* Allocate blkgrp based on gdsize (for 64-bit support). */
1606 blkgrp = zalloc(get_fs()->gdsize);
1607 if (!blkgrp)
1608 return 0;
1609
1610 /* It is easier to calculate if the first inode is 0. */
1611 ino--;
1612 if ( le32_to_cpu(sblock->inodes_per_group) == 0 || fs->inodesz == 0) {
1613 free(blkgrp);
1614 return 0;
1615 }
1616 status = ext4fs_blockgroup(data, ino / le32_to_cpu
1617 (sblock->inodes_per_group), blkgrp);
1618 if (status == 0) {
1619 free(blkgrp);
1620 return 0;
1621 }
1622
1623 inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
1624 if ( inodes_per_block == 0 ) {
1625 free(blkgrp);
1626 return 0;
1627 }
1628 blkno = ext4fs_bg_get_inode_table_id(blkgrp, fs) +
1629 (ino % le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
1630 blkoff = (ino % inodes_per_block) * fs->inodesz;
1631
1632 /* Free blkgrp as it is no longer required. */
1633 free(blkgrp);
1634
1635 /* Read the inode. */
1636 status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) -
1637 log2blksz), blkoff,
1638 sizeof(struct ext2_inode), (char *)inode);
1639 if (status == 0)
1640 return 0;
1641
1642 return 1;
1643 }
1644
read_allocated_block(struct ext2_inode * inode,int fileblock,struct ext_block_cache * cache)1645 long int read_allocated_block(struct ext2_inode *inode, int fileblock,
1646 struct ext_block_cache *cache)
1647 {
1648 long int blknr;
1649 int blksz;
1650 int log2_blksz;
1651 int status;
1652 long int rblock;
1653 long int perblock_parent;
1654 long int perblock_child;
1655 unsigned long long start;
1656 /* get the blocksize of the filesystem */
1657 blksz = EXT2_BLOCK_SIZE(ext4fs_root);
1658 log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root)
1659 - get_fs()->dev_desc->log2blksz;
1660
1661 if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
1662 long int startblock, endblock;
1663 struct ext_block_cache *c, cd;
1664 struct ext4_extent_header *ext_block;
1665 struct ext4_extent *extent;
1666 int i;
1667
1668 if (cache) {
1669 c = cache;
1670 } else {
1671 c = &cd;
1672 ext_cache_init(c);
1673 }
1674 ext_block =
1675 ext4fs_get_extent_block(ext4fs_root, c,
1676 (struct ext4_extent_header *)
1677 inode->b.blocks.dir_blocks,
1678 fileblock, log2_blksz);
1679 if (!ext_block) {
1680 printf("invalid extent block\n");
1681 if (!cache)
1682 ext_cache_fini(c);
1683 return -EINVAL;
1684 }
1685
1686 extent = (struct ext4_extent *)(ext_block + 1);
1687
1688 for (i = 0; i < le16_to_cpu(ext_block->eh_entries); i++) {
1689 startblock = le32_to_cpu(extent[i].ee_block);
1690 endblock = startblock + le16_to_cpu(extent[i].ee_len);
1691
1692 if (startblock > fileblock) {
1693 /* Sparse file */
1694 if (!cache)
1695 ext_cache_fini(c);
1696 return 0;
1697
1698 } else if (fileblock < endblock) {
1699 start = le16_to_cpu(extent[i].ee_start_hi);
1700 start = (start << 32) +
1701 le32_to_cpu(extent[i].ee_start_lo);
1702 if (!cache)
1703 ext_cache_fini(c);
1704 return (fileblock - startblock) + start;
1705 }
1706 }
1707
1708 if (!cache)
1709 ext_cache_fini(c);
1710 return 0;
1711 }
1712
1713 /* Direct blocks. */
1714 if (fileblock < INDIRECT_BLOCKS)
1715 blknr = le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]);
1716
1717 /* Indirect. */
1718 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
1719 if (ext4fs_indir1_block == NULL) {
1720 ext4fs_indir1_block = zalloc(blksz);
1721 if (ext4fs_indir1_block == NULL) {
1722 printf("** SI ext2fs read block (indir 1)"
1723 "malloc failed. **\n");
1724 return -1;
1725 }
1726 ext4fs_indir1_size = blksz;
1727 ext4fs_indir1_blkno = -1;
1728 }
1729 if (blksz != ext4fs_indir1_size) {
1730 free(ext4fs_indir1_block);
1731 ext4fs_indir1_block = NULL;
1732 ext4fs_indir1_size = 0;
1733 ext4fs_indir1_blkno = -1;
1734 ext4fs_indir1_block = zalloc(blksz);
1735 if (ext4fs_indir1_block == NULL) {
1736 printf("** SI ext2fs read block (indir 1):"
1737 "malloc failed. **\n");
1738 return -1;
1739 }
1740 ext4fs_indir1_size = blksz;
1741 }
1742 if ((le32_to_cpu(inode->b.blocks.indir_block) <<
1743 log2_blksz) != ext4fs_indir1_blkno) {
1744 status =
1745 ext4fs_devread((lbaint_t)le32_to_cpu
1746 (inode->b.blocks.
1747 indir_block) << log2_blksz, 0,
1748 blksz, (char *)ext4fs_indir1_block);
1749 if (status == 0) {
1750 printf("** SI ext2fs read block (indir 1)"
1751 "failed. **\n");
1752 return -1;
1753 }
1754 ext4fs_indir1_blkno =
1755 le32_to_cpu(inode->b.blocks.
1756 indir_block) << log2_blksz;
1757 }
1758 blknr = le32_to_cpu(ext4fs_indir1_block
1759 [fileblock - INDIRECT_BLOCKS]);
1760 }
1761 /* Double indirect. */
1762 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 *
1763 (blksz / 4 + 1)))) {
1764
1765 long int perblock = blksz / 4;
1766 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4);
1767
1768 if (ext4fs_indir1_block == NULL) {
1769 ext4fs_indir1_block = zalloc(blksz);
1770 if (ext4fs_indir1_block == NULL) {
1771 printf("** DI ext2fs read block (indir 2 1)"
1772 "malloc failed. **\n");
1773 return -1;
1774 }
1775 ext4fs_indir1_size = blksz;
1776 ext4fs_indir1_blkno = -1;
1777 }
1778 if (blksz != ext4fs_indir1_size) {
1779 free(ext4fs_indir1_block);
1780 ext4fs_indir1_block = NULL;
1781 ext4fs_indir1_size = 0;
1782 ext4fs_indir1_blkno = -1;
1783 ext4fs_indir1_block = zalloc(blksz);
1784 if (ext4fs_indir1_block == NULL) {
1785 printf("** DI ext2fs read block (indir 2 1)"
1786 "malloc failed. **\n");
1787 return -1;
1788 }
1789 ext4fs_indir1_size = blksz;
1790 }
1791 if ((le32_to_cpu(inode->b.blocks.double_indir_block) <<
1792 log2_blksz) != ext4fs_indir1_blkno) {
1793 status =
1794 ext4fs_devread((lbaint_t)le32_to_cpu
1795 (inode->b.blocks.
1796 double_indir_block) << log2_blksz,
1797 0, blksz,
1798 (char *)ext4fs_indir1_block);
1799 if (status == 0) {
1800 printf("** DI ext2fs read block (indir 2 1)"
1801 "failed. **\n");
1802 return -1;
1803 }
1804 ext4fs_indir1_blkno =
1805 le32_to_cpu(inode->b.blocks.double_indir_block) <<
1806 log2_blksz;
1807 }
1808
1809 if (ext4fs_indir2_block == NULL) {
1810 ext4fs_indir2_block = zalloc(blksz);
1811 if (ext4fs_indir2_block == NULL) {
1812 printf("** DI ext2fs read block (indir 2 2)"
1813 "malloc failed. **\n");
1814 return -1;
1815 }
1816 ext4fs_indir2_size = blksz;
1817 ext4fs_indir2_blkno = -1;
1818 }
1819 if (blksz != ext4fs_indir2_size) {
1820 free(ext4fs_indir2_block);
1821 ext4fs_indir2_block = NULL;
1822 ext4fs_indir2_size = 0;
1823 ext4fs_indir2_blkno = -1;
1824 ext4fs_indir2_block = zalloc(blksz);
1825 if (ext4fs_indir2_block == NULL) {
1826 printf("** DI ext2fs read block (indir 2 2)"
1827 "malloc failed. **\n");
1828 return -1;
1829 }
1830 ext4fs_indir2_size = blksz;
1831 }
1832 if ((le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) <<
1833 log2_blksz) != ext4fs_indir2_blkno) {
1834 status = ext4fs_devread((lbaint_t)le32_to_cpu
1835 (ext4fs_indir1_block
1836 [rblock /
1837 perblock]) << log2_blksz, 0,
1838 blksz,
1839 (char *)ext4fs_indir2_block);
1840 if (status == 0) {
1841 printf("** DI ext2fs read block (indir 2 2)"
1842 "failed. **\n");
1843 return -1;
1844 }
1845 ext4fs_indir2_blkno =
1846 le32_to_cpu(ext4fs_indir1_block[rblock
1847 /
1848 perblock]) <<
1849 log2_blksz;
1850 }
1851 blknr = le32_to_cpu(ext4fs_indir2_block[rblock % perblock]);
1852 }
1853 /* Tripple indirect. */
1854 else {
1855 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 +
1856 (blksz / 4 * blksz / 4));
1857 perblock_child = blksz / 4;
1858 perblock_parent = ((blksz / 4) * (blksz / 4));
1859
1860 if (ext4fs_indir1_block == NULL) {
1861 ext4fs_indir1_block = zalloc(blksz);
1862 if (ext4fs_indir1_block == NULL) {
1863 printf("** TI ext2fs read block (indir 2 1)"
1864 "malloc failed. **\n");
1865 return -1;
1866 }
1867 ext4fs_indir1_size = blksz;
1868 ext4fs_indir1_blkno = -1;
1869 }
1870 if (blksz != ext4fs_indir1_size) {
1871 free(ext4fs_indir1_block);
1872 ext4fs_indir1_block = NULL;
1873 ext4fs_indir1_size = 0;
1874 ext4fs_indir1_blkno = -1;
1875 ext4fs_indir1_block = zalloc(blksz);
1876 if (ext4fs_indir1_block == NULL) {
1877 printf("** TI ext2fs read block (indir 2 1)"
1878 "malloc failed. **\n");
1879 return -1;
1880 }
1881 ext4fs_indir1_size = blksz;
1882 }
1883 if ((le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1884 log2_blksz) != ext4fs_indir1_blkno) {
1885 status = ext4fs_devread
1886 ((lbaint_t)
1887 le32_to_cpu(inode->b.blocks.triple_indir_block)
1888 << log2_blksz, 0, blksz,
1889 (char *)ext4fs_indir1_block);
1890 if (status == 0) {
1891 printf("** TI ext2fs read block (indir 2 1)"
1892 "failed. **\n");
1893 return -1;
1894 }
1895 ext4fs_indir1_blkno =
1896 le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1897 log2_blksz;
1898 }
1899
1900 if (ext4fs_indir2_block == NULL) {
1901 ext4fs_indir2_block = zalloc(blksz);
1902 if (ext4fs_indir2_block == NULL) {
1903 printf("** TI ext2fs read block (indir 2 2)"
1904 "malloc failed. **\n");
1905 return -1;
1906 }
1907 ext4fs_indir2_size = blksz;
1908 ext4fs_indir2_blkno = -1;
1909 }
1910 if (blksz != ext4fs_indir2_size) {
1911 free(ext4fs_indir2_block);
1912 ext4fs_indir2_block = NULL;
1913 ext4fs_indir2_size = 0;
1914 ext4fs_indir2_blkno = -1;
1915 ext4fs_indir2_block = zalloc(blksz);
1916 if (ext4fs_indir2_block == NULL) {
1917 printf("** TI ext2fs read block (indir 2 2)"
1918 "malloc failed. **\n");
1919 return -1;
1920 }
1921 ext4fs_indir2_size = blksz;
1922 }
1923 if ((le32_to_cpu(ext4fs_indir1_block[rblock /
1924 perblock_parent]) <<
1925 log2_blksz)
1926 != ext4fs_indir2_blkno) {
1927 status = ext4fs_devread((lbaint_t)le32_to_cpu
1928 (ext4fs_indir1_block
1929 [rblock /
1930 perblock_parent]) <<
1931 log2_blksz, 0, blksz,
1932 (char *)ext4fs_indir2_block);
1933 if (status == 0) {
1934 printf("** TI ext2fs read block (indir 2 2)"
1935 "failed. **\n");
1936 return -1;
1937 }
1938 ext4fs_indir2_blkno =
1939 le32_to_cpu(ext4fs_indir1_block[rblock /
1940 perblock_parent])
1941 << log2_blksz;
1942 }
1943
1944 if (ext4fs_indir3_block == NULL) {
1945 ext4fs_indir3_block = zalloc(blksz);
1946 if (ext4fs_indir3_block == NULL) {
1947 printf("** TI ext2fs read block (indir 2 2)"
1948 "malloc failed. **\n");
1949 return -1;
1950 }
1951 ext4fs_indir3_size = blksz;
1952 ext4fs_indir3_blkno = -1;
1953 }
1954 if (blksz != ext4fs_indir3_size) {
1955 free(ext4fs_indir3_block);
1956 ext4fs_indir3_block = NULL;
1957 ext4fs_indir3_size = 0;
1958 ext4fs_indir3_blkno = -1;
1959 ext4fs_indir3_block = zalloc(blksz);
1960 if (ext4fs_indir3_block == NULL) {
1961 printf("** TI ext2fs read block (indir 2 2)"
1962 "malloc failed. **\n");
1963 return -1;
1964 }
1965 ext4fs_indir3_size = blksz;
1966 }
1967 if ((le32_to_cpu(ext4fs_indir2_block[rblock
1968 /
1969 perblock_child]) <<
1970 log2_blksz) != ext4fs_indir3_blkno) {
1971 status =
1972 ext4fs_devread((lbaint_t)le32_to_cpu
1973 (ext4fs_indir2_block
1974 [(rblock / perblock_child)
1975 % (blksz / 4)]) << log2_blksz, 0,
1976 blksz, (char *)ext4fs_indir3_block);
1977 if (status == 0) {
1978 printf("** TI ext2fs read block (indir 2 2)"
1979 "failed. **\n");
1980 return -1;
1981 }
1982 ext4fs_indir3_blkno =
1983 le32_to_cpu(ext4fs_indir2_block[(rblock /
1984 perblock_child) %
1985 (blksz /
1986 4)]) <<
1987 log2_blksz;
1988 }
1989
1990 blknr = le32_to_cpu(ext4fs_indir3_block
1991 [rblock % perblock_child]);
1992 }
1993 debug("read_allocated_block %ld\n", blknr);
1994
1995 return blknr;
1996 }
1997
1998 /**
1999 * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's
2000 * global pointers
2001 *
2002 * This function assures that for a file with the same name but different size
2003 * the sequential store on the ext4 filesystem will be correct.
2004 *
2005 * In this function the global data, responsible for internal representation
2006 * of the ext4 data are initialized to the reset state. Without this, during
2007 * replacement of the smaller file with the bigger truncation of new file was
2008 * performed.
2009 */
ext4fs_reinit_global(void)2010 void ext4fs_reinit_global(void)
2011 {
2012 if (ext4fs_indir1_block != NULL) {
2013 free(ext4fs_indir1_block);
2014 ext4fs_indir1_block = NULL;
2015 ext4fs_indir1_size = 0;
2016 ext4fs_indir1_blkno = -1;
2017 }
2018 if (ext4fs_indir2_block != NULL) {
2019 free(ext4fs_indir2_block);
2020 ext4fs_indir2_block = NULL;
2021 ext4fs_indir2_size = 0;
2022 ext4fs_indir2_blkno = -1;
2023 }
2024 if (ext4fs_indir3_block != NULL) {
2025 free(ext4fs_indir3_block);
2026 ext4fs_indir3_block = NULL;
2027 ext4fs_indir3_size = 0;
2028 ext4fs_indir3_blkno = -1;
2029 }
2030 }
ext4fs_close(void)2031 void ext4fs_close(void)
2032 {
2033 if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) {
2034 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen);
2035 ext4fs_file = NULL;
2036 }
2037 if (ext4fs_root != NULL) {
2038 free(ext4fs_root);
2039 ext4fs_root = NULL;
2040 }
2041
2042 ext4fs_reinit_global();
2043 }
2044
ext4fs_iterate_dir(struct ext2fs_node * dir,char * name,struct ext2fs_node ** fnode,int * ftype)2045 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
2046 struct ext2fs_node **fnode, int *ftype)
2047 {
2048 unsigned int fpos = 0;
2049 int status;
2050 loff_t actread;
2051
2052 #ifdef DEBUG
2053 if (name != NULL)
2054 printf("Iterate dir %s\n", name);
2055 #endif /* of DEBUG */
2056 if (!dir->inode_read) {
2057 status = ext4fs_read_inode(dir->data, dir->ino, &dir->inode);
2058 if (status == 0)
2059 return 0;
2060 }
2061 /* Search the file. */
2062 while (fpos < le32_to_cpu(dir->inode.size)) {
2063 struct ext2_dirent dirent;
2064
2065 status = ext4fs_read_file(dir, fpos,
2066 sizeof(struct ext2_dirent),
2067 (char *)&dirent, &actread);
2068 if (status < 0)
2069 return 0;
2070
2071 if (dirent.direntlen == 0) {
2072 printf("Failed to iterate over directory %s\n", name);
2073 return 0;
2074 }
2075
2076 if (dirent.namelen != 0) {
2077 char filename[dirent.namelen + 1];
2078 struct ext2fs_node *fdiro;
2079 int type = FILETYPE_UNKNOWN;
2080
2081 status = ext4fs_read_file(dir,
2082 fpos +
2083 sizeof(struct ext2_dirent),
2084 dirent.namelen, filename,
2085 &actread);
2086 if (status < 0)
2087 return 0;
2088
2089 fdiro = zalloc(sizeof(struct ext2fs_node));
2090 if (!fdiro)
2091 return 0;
2092
2093 fdiro->data = dir->data;
2094 fdiro->ino = le32_to_cpu(dirent.inode);
2095
2096 filename[dirent.namelen] = '\0';
2097
2098 if (dirent.filetype != FILETYPE_UNKNOWN) {
2099 fdiro->inode_read = 0;
2100
2101 if (dirent.filetype == FILETYPE_DIRECTORY)
2102 type = FILETYPE_DIRECTORY;
2103 else if (dirent.filetype == FILETYPE_SYMLINK)
2104 type = FILETYPE_SYMLINK;
2105 else if (dirent.filetype == FILETYPE_REG)
2106 type = FILETYPE_REG;
2107 } else {
2108 status = ext4fs_read_inode(dir->data,
2109 le32_to_cpu
2110 (dirent.inode),
2111 &fdiro->inode);
2112 if (status == 0) {
2113 free(fdiro);
2114 return 0;
2115 }
2116 fdiro->inode_read = 1;
2117
2118 if ((le16_to_cpu(fdiro->inode.mode) &
2119 FILETYPE_INO_MASK) ==
2120 FILETYPE_INO_DIRECTORY) {
2121 type = FILETYPE_DIRECTORY;
2122 } else if ((le16_to_cpu(fdiro->inode.mode)
2123 & FILETYPE_INO_MASK) ==
2124 FILETYPE_INO_SYMLINK) {
2125 type = FILETYPE_SYMLINK;
2126 } else if ((le16_to_cpu(fdiro->inode.mode)
2127 & FILETYPE_INO_MASK) ==
2128 FILETYPE_INO_REG) {
2129 type = FILETYPE_REG;
2130 }
2131 }
2132 #ifdef DEBUG
2133 printf("iterate >%s<\n", filename);
2134 #endif /* of DEBUG */
2135 if ((name != NULL) && (fnode != NULL)
2136 && (ftype != NULL)) {
2137 if (strcmp(filename, name) == 0) {
2138 *ftype = type;
2139 *fnode = fdiro;
2140 return 1;
2141 }
2142 }
2143 free(fdiro);
2144 }
2145 fpos += le16_to_cpu(dirent.direntlen);
2146 }
2147 return 0;
2148 }
2149
ext4fs_read_symlink(struct ext2fs_node * node)2150 static char *ext4fs_read_symlink(struct ext2fs_node *node)
2151 {
2152 char *symlink;
2153 struct ext2fs_node *diro = node;
2154 int status;
2155 loff_t actread;
2156 size_t alloc_size;
2157
2158 if (!diro->inode_read) {
2159 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
2160 if (status == 0)
2161 return NULL;
2162 }
2163
2164 if (__builtin_add_overflow(le32_to_cpu(diro->inode.size), 1, &alloc_size))
2165 return NULL;
2166
2167 symlink = zalloc(alloc_size);
2168 if (!symlink)
2169 return NULL;
2170
2171 if (le32_to_cpu(diro->inode.size) < sizeof(diro->inode.b.symlink)) {
2172 strncpy(symlink, diro->inode.b.symlink,
2173 le32_to_cpu(diro->inode.size));
2174 } else {
2175 status = ext4fs_read_file(diro, 0,
2176 le32_to_cpu(diro->inode.size),
2177 symlink, &actread);
2178 if ((status < 0) || (actread == 0)) {
2179 free(symlink);
2180 return NULL;
2181 }
2182 }
2183 symlink[le32_to_cpu(diro->inode.size)] = '\0';
2184 return symlink;
2185 }
2186
ext4fs_find_file1(const char * currpath,struct ext2fs_node * currroot,struct ext2fs_node ** currfound,int * foundtype)2187 int ext4fs_find_file1(const char *currpath, struct ext2fs_node *currroot,
2188 struct ext2fs_node **currfound, int *foundtype)
2189 {
2190 char fpath[strlen(currpath) + 1];
2191 char *name = fpath;
2192 char *next;
2193 int status;
2194 int type = FILETYPE_DIRECTORY;
2195 struct ext2fs_node *currnode = currroot;
2196 struct ext2fs_node *oldnode = currroot;
2197
2198 strncpy(fpath, currpath, strlen(currpath) + 1);
2199
2200 /* Remove all leading slashes. */
2201 while (*name == '/')
2202 name++;
2203
2204 if (!*name) {
2205 *currfound = currnode;
2206 return 1;
2207 }
2208
2209 for (;;) {
2210 int found;
2211
2212 /* Extract the actual part from the pathname. */
2213 next = strchr(name, '/');
2214 if (next) {
2215 /* Remove all leading slashes. */
2216 while (*next == '/')
2217 *(next++) = '\0';
2218 }
2219
2220 if (type != FILETYPE_DIRECTORY) {
2221 ext4fs_free_node(currnode, currroot);
2222 return 0;
2223 }
2224
2225 oldnode = currnode;
2226
2227 /* Iterate over the directory. */
2228 found = ext4fs_iterate_dir(currnode, name, &currnode, &type);
2229 if (found == 0)
2230 return 0;
2231
2232 if (found == -1)
2233 break;
2234
2235 /* Read in the symlink and follow it. */
2236 if (type == FILETYPE_SYMLINK) {
2237 char *symlink;
2238
2239 /* Test if the symlink does not loop. */
2240 if (++symlinknest == 8) {
2241 ext4fs_free_node(currnode, currroot);
2242 ext4fs_free_node(oldnode, currroot);
2243 return 0;
2244 }
2245
2246 symlink = ext4fs_read_symlink(currnode);
2247 ext4fs_free_node(currnode, currroot);
2248
2249 if (!symlink) {
2250 ext4fs_free_node(oldnode, currroot);
2251 return 0;
2252 }
2253
2254 debug("Got symlink >%s<\n", symlink);
2255
2256 if (symlink[0] == '/') {
2257 ext4fs_free_node(oldnode, currroot);
2258 oldnode = &ext4fs_root->diropen;
2259 }
2260
2261 /* Lookup the node the symlink points to. */
2262 status = ext4fs_find_file1(symlink, oldnode,
2263 &currnode, &type);
2264
2265 free(symlink);
2266
2267 if (status == 0) {
2268 ext4fs_free_node(oldnode, currroot);
2269 return 0;
2270 }
2271 }
2272
2273 ext4fs_free_node(oldnode, currroot);
2274
2275 /* Found the node! */
2276 if (!next || *next == '\0') {
2277 *currfound = currnode;
2278 *foundtype = type;
2279 return 1;
2280 }
2281 name = next;
2282 }
2283 return -1;
2284 }
2285
ext4fs_find_file(const char * path,struct ext2fs_node * rootnode,struct ext2fs_node ** foundnode,int expecttype)2286 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode,
2287 struct ext2fs_node **foundnode, int expecttype)
2288 {
2289 int status;
2290 int foundtype = FILETYPE_DIRECTORY;
2291
2292 symlinknest = 0;
2293 if (!path)
2294 return 0;
2295
2296 status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype);
2297 if (status == 0)
2298 return 0;
2299
2300 /* Check if the node that was found was of the expected type. */
2301 if ((expecttype == FILETYPE_REG) && (foundtype != expecttype))
2302 return 0;
2303 else if ((expecttype == FILETYPE_DIRECTORY)
2304 && (foundtype != expecttype))
2305 return 0;
2306
2307 return 1;
2308 }
2309
ext4fs_open(const char * filename,loff_t * len)2310 int ext4fs_open(const char *filename, loff_t *len)
2311 {
2312 struct ext2fs_node *fdiro = NULL;
2313 int status;
2314
2315 if (ext4fs_root == NULL)
2316 return -1;
2317
2318 ext4fs_file = NULL;
2319 status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro,
2320 FILETYPE_REG);
2321 if (status == 0)
2322 goto fail;
2323
2324 if (!fdiro->inode_read) {
2325 status = ext4fs_read_inode(fdiro->data, fdiro->ino,
2326 &fdiro->inode);
2327 if (status == 0)
2328 goto fail;
2329 }
2330 *len = le32_to_cpu(fdiro->inode.size);
2331 ext4fs_file = fdiro;
2332
2333 return 0;
2334 fail:
2335 ext4fs_free_node(fdiro, &ext4fs_root->diropen);
2336
2337 return -1;
2338 }
2339
ext4fs_mount(void)2340 int ext4fs_mount(void)
2341 {
2342 struct ext2_data *data;
2343 int status;
2344 struct ext_filesystem *fs = get_fs();
2345 data = zalloc(SUPERBLOCK_SIZE);
2346 if (!data)
2347 return 0;
2348
2349 /* Read the superblock. */
2350 status = ext4_read_superblock((char *)&data->sblock);
2351
2352 if (status == 0)
2353 goto fail;
2354
2355 /* Make sure this is an ext2 filesystem. */
2356 if (le16_to_cpu(data->sblock.magic) != EXT2_MAGIC)
2357 goto fail_noerr;
2358
2359 if (le32_to_cpu(data->sblock.revision_level) == 0) {
2360 fs->inodesz = 128;
2361 fs->gdsize = 32;
2362 } else {
2363 int missing = __le32_to_cpu(data->sblock.feature_incompat) &
2364 ~(EXT4_FEATURE_INCOMPAT_SUPP |
2365 EXT4_FEATURE_INCOMPAT_SUPP_LAZY_RO);
2366
2367 if (missing) {
2368 /*
2369 * This code used to be relaxed about feature flags.
2370 * We don't stop the mount to avoid breaking existing setups.
2371 * But, incompatible features can cause serious read errors.
2372 */
2373 log_err("fs uses incompatible features: %08x, ignoring\n",
2374 missing);
2375 }
2376
2377 debug("EXT4 features COMPAT: %08x INCOMPAT: %08x RO_COMPAT: %08x\n",
2378 __le32_to_cpu(data->sblock.feature_compatibility),
2379 __le32_to_cpu(data->sblock.feature_incompat),
2380 __le32_to_cpu(data->sblock.feature_ro_compat));
2381
2382 fs->inodesz = le16_to_cpu(data->sblock.inode_size);
2383 fs->gdsize = le32_to_cpu(data->sblock.feature_incompat) &
2384 EXT4_FEATURE_INCOMPAT_64BIT ?
2385 le16_to_cpu(data->sblock.descriptor_size) : 32;
2386 }
2387
2388 debug("EXT2 rev %d, inode_size %d, descriptor size %d\n",
2389 le32_to_cpu(data->sblock.revision_level),
2390 fs->inodesz, fs->gdsize);
2391
2392 data->diropen.data = data;
2393 data->diropen.ino = 2;
2394 data->diropen.inode_read = 1;
2395 data->inode = &data->diropen.inode;
2396
2397 status = ext4fs_read_inode(data, 2, data->inode);
2398 if (status == 0)
2399 goto fail;
2400
2401 ext4fs_root = data;
2402
2403 return 1;
2404 fail:
2405 log_debug("Failed to mount ext2 filesystem...\n");
2406 fail_noerr:
2407 free(data);
2408 ext4fs_root = NULL;
2409
2410 return 0;
2411 }
2412