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Donggeun Kimc30a15e2011-10-24 21:15:28 +00001/*
2 * fat_write.c
3 *
4 * R/W (V)FAT 12/16/32 filesystem implementation by Donggeun Kim
5 *
Wolfgang Denk1a459662013-07-08 09:37:19 +02006 * SPDX-License-Identifier: GPL-2.0+
Donggeun Kimc30a15e2011-10-24 21:15:28 +00007 */
8
9#include <common.h>
10#include <command.h>
11#include <config.h>
12#include <fat.h>
13#include <asm/byteorder.h>
14#include <part.h>
Richard Genoudfb7e16c2012-12-13 00:47:36 +000015#include <linux/ctype.h>
Donggeun Kimc30a15e2011-10-24 21:15:28 +000016#include "fat.c"
17
18static void uppercase(char *str, int len)
19{
20 int i;
21
22 for (i = 0; i < len; i++) {
Richard Genoudfb7e16c2012-12-13 00:47:36 +000023 *str = toupper(*str);
Donggeun Kimc30a15e2011-10-24 21:15:28 +000024 str++;
25 }
26}
27
28static int total_sector;
Donggeun Kim079df722012-03-22 04:38:55 +000029static int disk_write(__u32 block, __u32 nr_blocks, void *buf)
Donggeun Kimc30a15e2011-10-24 21:15:28 +000030{
Donggeun Kim079df722012-03-22 04:38:55 +000031 if (!cur_dev || !cur_dev->block_write)
Donggeun Kimc30a15e2011-10-24 21:15:28 +000032 return -1;
33
Donggeun Kim079df722012-03-22 04:38:55 +000034 if (cur_part_info.start + block + nr_blocks >
35 cur_part_info.start + total_sector) {
Donggeun Kimc30a15e2011-10-24 21:15:28 +000036 printf("error: overflow occurs\n");
37 return -1;
38 }
39
Donggeun Kim079df722012-03-22 04:38:55 +000040 return cur_dev->block_write(cur_dev->dev,
41 cur_part_info.start + block, nr_blocks, buf);
Donggeun Kimc30a15e2011-10-24 21:15:28 +000042}
43
44/*
45 * Set short name in directory entry
46 */
47static void set_name(dir_entry *dirent, const char *filename)
48{
49 char s_name[VFAT_MAXLEN_BYTES];
50 char *period;
51 int period_location, len, i, ext_num;
52
53 if (filename == NULL)
54 return;
55
56 len = strlen(filename);
57 if (len == 0)
58 return;
59
60 memcpy(s_name, filename, len);
61 uppercase(s_name, len);
62
63 period = strchr(s_name, '.');
64 if (period == NULL) {
65 period_location = len;
66 ext_num = 0;
67 } else {
68 period_location = period - s_name;
69 ext_num = len - period_location - 1;
70 }
71
72 /* Pad spaces when the length of file name is shorter than eight */
73 if (period_location < 8) {
74 memcpy(dirent->name, s_name, period_location);
75 for (i = period_location; i < 8; i++)
76 dirent->name[i] = ' ';
77 } else if (period_location == 8) {
78 memcpy(dirent->name, s_name, period_location);
79 } else {
80 memcpy(dirent->name, s_name, 6);
81 dirent->name[6] = '~';
82 dirent->name[7] = '1';
83 }
84
85 if (ext_num < 3) {
86 memcpy(dirent->ext, s_name + period_location + 1, ext_num);
87 for (i = ext_num; i < 3; i++)
88 dirent->ext[i] = ' ';
89 } else
90 memcpy(dirent->ext, s_name + period_location + 1, 3);
91
92 debug("name : %s\n", dirent->name);
93 debug("ext : %s\n", dirent->ext);
94}
95
Donggeun Kim627182e2011-12-20 18:34:27 +000096static __u8 num_of_fats;
Donggeun Kimc30a15e2011-10-24 21:15:28 +000097/*
98 * Write fat buffer into block device
99 */
100static int flush_fat_buffer(fsdata *mydata)
101{
102 int getsize = FATBUFBLOCKS;
103 __u32 fatlength = mydata->fatlength;
104 __u8 *bufptr = mydata->fatbuf;
105 __u32 startblock = mydata->fatbufnum * FATBUFBLOCKS;
106
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000107 startblock += mydata->fat_sect;
108
109 if (getsize > fatlength)
110 getsize = fatlength;
111
112 /* Write FAT buf */
113 if (disk_write(startblock, getsize, bufptr) < 0) {
114 debug("error: writing FAT blocks\n");
115 return -1;
116 }
117
Donggeun Kim627182e2011-12-20 18:34:27 +0000118 if (num_of_fats == 2) {
119 /* Update corresponding second FAT blocks */
120 startblock += mydata->fatlength;
121 if (disk_write(startblock, getsize, bufptr) < 0) {
122 debug("error: writing second FAT blocks\n");
123 return -1;
124 }
125 }
126
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000127 return 0;
128}
129
130/*
131 * Get the entry at index 'entry' in a FAT (12/16/32) table.
132 * On failure 0x00 is returned.
133 * When bufnum is changed, write back the previous fatbuf to the disk.
134 */
135static __u32 get_fatent_value(fsdata *mydata, __u32 entry)
136{
137 __u32 bufnum;
138 __u32 off16, offset;
139 __u32 ret = 0x00;
140 __u16 val1, val2;
141
142 switch (mydata->fatsize) {
143 case 32:
144 bufnum = entry / FAT32BUFSIZE;
145 offset = entry - bufnum * FAT32BUFSIZE;
146 break;
147 case 16:
148 bufnum = entry / FAT16BUFSIZE;
149 offset = entry - bufnum * FAT16BUFSIZE;
150 break;
151 case 12:
152 bufnum = entry / FAT12BUFSIZE;
153 offset = entry - bufnum * FAT12BUFSIZE;
154 break;
155
156 default:
157 /* Unsupported FAT size */
158 return ret;
159 }
160
161 debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
162 mydata->fatsize, entry, entry, offset, offset);
163
164 /* Read a new block of FAT entries into the cache. */
165 if (bufnum != mydata->fatbufnum) {
166 int getsize = FATBUFBLOCKS;
167 __u8 *bufptr = mydata->fatbuf;
168 __u32 fatlength = mydata->fatlength;
169 __u32 startblock = bufnum * FATBUFBLOCKS;
170
171 if (getsize > fatlength)
172 getsize = fatlength;
173
174 fatlength *= mydata->sect_size; /* We want it in bytes now */
175 startblock += mydata->fat_sect; /* Offset from start of disk */
176
177 /* Write back the fatbuf to the disk */
178 if (mydata->fatbufnum != -1) {
179 if (flush_fat_buffer(mydata) < 0)
180 return -1;
181 }
182
183 if (disk_read(startblock, getsize, bufptr) < 0) {
184 debug("Error reading FAT blocks\n");
185 return ret;
186 }
187 mydata->fatbufnum = bufnum;
188 }
189
190 /* Get the actual entry from the table */
191 switch (mydata->fatsize) {
192 case 32:
193 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
194 break;
195 case 16:
196 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
197 break;
198 case 12:
199 off16 = (offset * 3) / 4;
200
201 switch (offset & 0x3) {
202 case 0:
203 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
204 ret &= 0xfff;
205 break;
206 case 1:
207 val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
208 val1 &= 0xf000;
209 val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
210 val2 &= 0x00ff;
211 ret = (val2 << 4) | (val1 >> 12);
212 break;
213 case 2:
214 val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
215 val1 &= 0xff00;
216 val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
217 val2 &= 0x000f;
218 ret = (val2 << 8) | (val1 >> 8);
219 break;
220 case 3:
221 ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
222 ret = (ret & 0xfff0) >> 4;
223 break;
224 default:
225 break;
226 }
227 break;
228 }
229 debug("FAT%d: ret: %08x, entry: %08x, offset: %04x\n",
230 mydata->fatsize, ret, entry, offset);
231
232 return ret;
233}
234
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000235/*
236 * Set the file name information from 'name' into 'slotptr',
237 */
238static int str2slot(dir_slot *slotptr, const char *name, int *idx)
239{
240 int j, end_idx = 0;
241
242 for (j = 0; j <= 8; j += 2) {
243 if (name[*idx] == 0x00) {
244 slotptr->name0_4[j] = 0;
245 slotptr->name0_4[j + 1] = 0;
246 end_idx++;
247 goto name0_4;
248 }
249 slotptr->name0_4[j] = name[*idx];
250 (*idx)++;
251 end_idx++;
252 }
253 for (j = 0; j <= 10; j += 2) {
254 if (name[*idx] == 0x00) {
255 slotptr->name5_10[j] = 0;
256 slotptr->name5_10[j + 1] = 0;
257 end_idx++;
258 goto name5_10;
259 }
260 slotptr->name5_10[j] = name[*idx];
261 (*idx)++;
262 end_idx++;
263 }
264 for (j = 0; j <= 2; j += 2) {
265 if (name[*idx] == 0x00) {
266 slotptr->name11_12[j] = 0;
267 slotptr->name11_12[j + 1] = 0;
268 end_idx++;
269 goto name11_12;
270 }
271 slotptr->name11_12[j] = name[*idx];
272 (*idx)++;
273 end_idx++;
274 }
275
276 if (name[*idx] == 0x00)
277 return 1;
278
279 return 0;
280/* Not used characters are filled with 0xff 0xff */
281name0_4:
282 for (; end_idx < 5; end_idx++) {
283 slotptr->name0_4[end_idx * 2] = 0xff;
284 slotptr->name0_4[end_idx * 2 + 1] = 0xff;
285 }
286 end_idx = 5;
287name5_10:
288 end_idx -= 5;
289 for (; end_idx < 6; end_idx++) {
290 slotptr->name5_10[end_idx * 2] = 0xff;
291 slotptr->name5_10[end_idx * 2 + 1] = 0xff;
292 }
293 end_idx = 11;
294name11_12:
295 end_idx -= 11;
296 for (; end_idx < 2; end_idx++) {
297 slotptr->name11_12[end_idx * 2] = 0xff;
298 slotptr->name11_12[end_idx * 2 + 1] = 0xff;
299 }
300
301 return 1;
302}
303
304static int is_next_clust(fsdata *mydata, dir_entry *dentptr);
305static void flush_dir_table(fsdata *mydata, dir_entry **dentptr);
306
307/*
308 * Fill dir_slot entries with appropriate name, id, and attr
309 * The real directory entry is returned by 'dentptr'
310 */
311static void
312fill_dir_slot(fsdata *mydata, dir_entry **dentptr, const char *l_name)
313{
Benoît Thébaudeau1170e632012-09-18 08:14:56 +0000314 dir_slot *slotptr = (dir_slot *)get_contents_vfatname_block;
Anatolij Gustschin8506eb82011-12-15 03:12:14 +0000315 __u8 counter = 0, checksum;
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000316 int idx = 0, ret;
317 char s_name[16];
318
319 /* Get short file name and checksum value */
320 strncpy(s_name, (*dentptr)->name, 16);
Marek Vasutff04f6d2012-10-09 07:20:22 +0000321 checksum = mkcksum((*dentptr)->name, (*dentptr)->ext);
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000322
323 do {
324 memset(slotptr, 0x00, sizeof(dir_slot));
325 ret = str2slot(slotptr, l_name, &idx);
326 slotptr->id = ++counter;
327 slotptr->attr = ATTR_VFAT;
328 slotptr->alias_checksum = checksum;
329 slotptr++;
330 } while (ret == 0);
331
332 slotptr--;
333 slotptr->id |= LAST_LONG_ENTRY_MASK;
334
335 while (counter >= 1) {
336 if (is_next_clust(mydata, *dentptr)) {
337 /* A new cluster is allocated for directory table */
338 flush_dir_table(mydata, dentptr);
339 }
340 memcpy(*dentptr, slotptr, sizeof(dir_slot));
341 (*dentptr)++;
342 slotptr--;
343 counter--;
344 }
345
346 if (is_next_clust(mydata, *dentptr)) {
347 /* A new cluster is allocated for directory table */
348 flush_dir_table(mydata, dentptr);
349 }
350}
351
352static __u32 dir_curclust;
353
354/*
355 * Extract the full long filename starting at 'retdent' (which is really
356 * a slot) into 'l_name'. If successful also copy the real directory entry
357 * into 'retdent'
358 * If additional adjacent cluster for directory entries is read into memory,
Benoît Thébaudeau1170e632012-09-18 08:14:56 +0000359 * then 'get_contents_vfatname_block' is copied into 'get_dentfromdir_block' and
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000360 * the location of the real directory entry is returned by 'retdent'
361 * Return 0 on success, -1 otherwise.
362 */
363static int
364get_long_file_name(fsdata *mydata, int curclust, __u8 *cluster,
365 dir_entry **retdent, char *l_name)
366{
367 dir_entry *realdent;
368 dir_slot *slotptr = (dir_slot *)(*retdent);
369 dir_slot *slotptr2 = NULL;
370 __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
371 PREFETCH_BLOCKS :
372 mydata->clust_size);
373 __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
374 int idx = 0, cur_position = 0;
375
376 if (counter > VFAT_MAXSEQ) {
377 debug("Error: VFAT name is too long\n");
378 return -1;
379 }
380
381 while ((__u8 *)slotptr < buflimit) {
382 if (counter == 0)
383 break;
384 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
385 return -1;
386 slotptr++;
387 counter--;
388 }
389
390 if ((__u8 *)slotptr >= buflimit) {
391 if (curclust == 0)
392 return -1;
393 curclust = get_fatent_value(mydata, dir_curclust);
394 if (CHECK_CLUST(curclust, mydata->fatsize)) {
395 debug("curclust: 0x%x\n", curclust);
396 printf("Invalid FAT entry\n");
397 return -1;
398 }
399
400 dir_curclust = curclust;
401
Benoît Thébaudeau1170e632012-09-18 08:14:56 +0000402 if (get_cluster(mydata, curclust, get_contents_vfatname_block,
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000403 mydata->clust_size * mydata->sect_size) != 0) {
404 debug("Error: reading directory block\n");
405 return -1;
406 }
407
Benoît Thébaudeau1170e632012-09-18 08:14:56 +0000408 slotptr2 = (dir_slot *)get_contents_vfatname_block;
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000409 while (counter > 0) {
410 if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
411 & 0xff) != counter)
412 return -1;
413 slotptr2++;
414 counter--;
415 }
416
417 /* Save the real directory entry */
418 realdent = (dir_entry *)slotptr2;
Benoît Thébaudeau1170e632012-09-18 08:14:56 +0000419 while ((__u8 *)slotptr2 > get_contents_vfatname_block) {
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000420 slotptr2--;
421 slot2str(slotptr2, l_name, &idx);
422 }
423 } else {
424 /* Save the real directory entry */
425 realdent = (dir_entry *)slotptr;
426 }
427
428 do {
429 slotptr--;
430 if (slot2str(slotptr, l_name, &idx))
431 break;
432 } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
433
434 l_name[idx] = '\0';
435 if (*l_name == DELETED_FLAG)
436 *l_name = '\0';
437 else if (*l_name == aRING)
438 *l_name = DELETED_FLAG;
439 downcase(l_name);
440
441 /* Return the real directory entry */
442 *retdent = realdent;
443
444 if (slotptr2) {
Benoît Thébaudeau1170e632012-09-18 08:14:56 +0000445 memcpy(get_dentfromdir_block, get_contents_vfatname_block,
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000446 mydata->clust_size * mydata->sect_size);
Benoît Thébaudeau1170e632012-09-18 08:14:56 +0000447 cur_position = (__u8 *)realdent - get_contents_vfatname_block;
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000448 *retdent = (dir_entry *) &get_dentfromdir_block[cur_position];
449 }
450
451 return 0;
452}
453
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000454/*
455 * Set the entry at index 'entry' in a FAT (16/32) table.
456 */
457static int set_fatent_value(fsdata *mydata, __u32 entry, __u32 entry_value)
458{
459 __u32 bufnum, offset;
460
461 switch (mydata->fatsize) {
462 case 32:
463 bufnum = entry / FAT32BUFSIZE;
464 offset = entry - bufnum * FAT32BUFSIZE;
465 break;
466 case 16:
467 bufnum = entry / FAT16BUFSIZE;
468 offset = entry - bufnum * FAT16BUFSIZE;
469 break;
470 default:
471 /* Unsupported FAT size */
472 return -1;
473 }
474
475 /* Read a new block of FAT entries into the cache. */
476 if (bufnum != mydata->fatbufnum) {
477 int getsize = FATBUFBLOCKS;
478 __u8 *bufptr = mydata->fatbuf;
479 __u32 fatlength = mydata->fatlength;
480 __u32 startblock = bufnum * FATBUFBLOCKS;
481
482 fatlength *= mydata->sect_size;
483 startblock += mydata->fat_sect;
484
485 if (getsize > fatlength)
486 getsize = fatlength;
487
488 if (mydata->fatbufnum != -1) {
489 if (flush_fat_buffer(mydata) < 0)
490 return -1;
491 }
492
493 if (disk_read(startblock, getsize, bufptr) < 0) {
494 debug("Error reading FAT blocks\n");
495 return -1;
496 }
497 mydata->fatbufnum = bufnum;
498 }
499
500 /* Set the actual entry */
501 switch (mydata->fatsize) {
502 case 32:
503 ((__u32 *) mydata->fatbuf)[offset] = cpu_to_le32(entry_value);
504 break;
505 case 16:
506 ((__u16 *) mydata->fatbuf)[offset] = cpu_to_le16(entry_value);
507 break;
508 default:
509 return -1;
510 }
511
512 return 0;
513}
514
515/*
516 * Determine the entry value at index 'entry' in a FAT (16/32) table
517 */
518static __u32 determine_fatent(fsdata *mydata, __u32 entry)
519{
520 __u32 next_fat, next_entry = entry + 1;
521
522 while (1) {
523 next_fat = get_fatent_value(mydata, next_entry);
524 if (next_fat == 0) {
525 set_fatent_value(mydata, entry, next_entry);
526 break;
527 }
528 next_entry++;
529 }
530 debug("FAT%d: entry: %08x, entry_value: %04x\n",
531 mydata->fatsize, entry, next_entry);
532
533 return next_entry;
534}
535
536/*
537 * Write at most 'size' bytes from 'buffer' into the specified cluster.
538 * Return 0 on success, -1 otherwise.
539 */
540static int
541set_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer,
542 unsigned long size)
543{
544 int idx = 0;
545 __u32 startsect;
546
547 if (clustnum > 0)
548 startsect = mydata->data_begin +
549 clustnum * mydata->clust_size;
550 else
551 startsect = mydata->rootdir_sect;
552
553 debug("clustnum: %d, startsect: %d\n", clustnum, startsect);
554
Wu, Josh6b8f1852013-07-24 17:55:30 +0800555 if ((size / mydata->sect_size) > 0) {
556 if (disk_write(startsect, size / mydata->sect_size, buffer) < 0) {
557 debug("Error writing data\n");
558 return -1;
559 }
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000560 }
561
562 if (size % mydata->sect_size) {
563 __u8 tmpbuf[mydata->sect_size];
564
565 idx = size / mydata->sect_size;
566 buffer += idx * mydata->sect_size;
567 memcpy(tmpbuf, buffer, size % mydata->sect_size);
568
569 if (disk_write(startsect + idx, 1, tmpbuf) < 0) {
570 debug("Error writing data\n");
571 return -1;
572 }
573
574 return 0;
575 }
576
577 return 0;
578}
579
580/*
581 * Find the first empty cluster
582 */
583static int find_empty_cluster(fsdata *mydata)
584{
585 __u32 fat_val, entry = 3;
586
587 while (1) {
588 fat_val = get_fatent_value(mydata, entry);
589 if (fat_val == 0)
590 break;
591 entry++;
592 }
593
594 return entry;
595}
596
597/*
598 * Write directory entries in 'get_dentfromdir_block' to block device
599 */
600static void flush_dir_table(fsdata *mydata, dir_entry **dentptr)
601{
602 int dir_newclust = 0;
603
604 if (set_cluster(mydata, dir_curclust,
605 get_dentfromdir_block,
606 mydata->clust_size * mydata->sect_size) != 0) {
607 printf("error: wrinting directory entry\n");
608 return;
609 }
610 dir_newclust = find_empty_cluster(mydata);
611 set_fatent_value(mydata, dir_curclust, dir_newclust);
612 if (mydata->fatsize == 32)
613 set_fatent_value(mydata, dir_newclust, 0xffffff8);
614 else if (mydata->fatsize == 16)
615 set_fatent_value(mydata, dir_newclust, 0xfff8);
616
617 dir_curclust = dir_newclust;
618
619 if (flush_fat_buffer(mydata) < 0)
620 return;
621
622 memset(get_dentfromdir_block, 0x00,
623 mydata->clust_size * mydata->sect_size);
624
625 *dentptr = (dir_entry *) get_dentfromdir_block;
626}
627
628/*
629 * Set empty cluster from 'entry' to the end of a file
630 */
631static int clear_fatent(fsdata *mydata, __u32 entry)
632{
633 __u32 fat_val;
634
635 while (1) {
636 fat_val = get_fatent_value(mydata, entry);
637 if (fat_val != 0)
638 set_fatent_value(mydata, entry, 0);
639 else
640 break;
641
642 if (fat_val == 0xfffffff || fat_val == 0xffff)
643 break;
644
645 entry = fat_val;
646 }
647
648 /* Flush fat buffer */
649 if (flush_fat_buffer(mydata) < 0)
650 return -1;
651
652 return 0;
653}
654
655/*
656 * Write at most 'maxsize' bytes from 'buffer' into
657 * the file associated with 'dentptr'
658 * Return the number of bytes read or -1 on fatal errors.
659 */
660static int
661set_contents(fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
662 unsigned long maxsize)
663{
664 unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
665 unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
666 __u32 curclust = START(dentptr);
667 __u32 endclust = 0, newclust = 0;
668 unsigned long actsize;
669
670 debug("Filesize: %ld bytes\n", filesize);
671
672 if (maxsize > 0 && filesize > maxsize)
673 filesize = maxsize;
674
675 debug("%ld bytes\n", filesize);
676
677 actsize = bytesperclust;
678 endclust = curclust;
679 do {
680 /* search for consecutive clusters */
681 while (actsize < filesize) {
682 newclust = determine_fatent(mydata, endclust);
683
684 if ((newclust - 1) != endclust)
685 goto getit;
686
687 if (CHECK_CLUST(newclust, mydata->fatsize)) {
688 debug("curclust: 0x%x\n", newclust);
689 debug("Invalid FAT entry\n");
690 return gotsize;
691 }
692 endclust = newclust;
693 actsize += bytesperclust;
694 }
695 /* actsize >= file size */
696 actsize -= bytesperclust;
697 /* set remaining clusters */
698 if (set_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
699 debug("error: writing cluster\n");
700 return -1;
701 }
702
703 /* set remaining bytes */
704 gotsize += (int)actsize;
705 filesize -= actsize;
706 buffer += actsize;
707 actsize = filesize;
708
709 if (set_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
710 debug("error: writing cluster\n");
711 return -1;
712 }
713 gotsize += actsize;
714
715 /* Mark end of file in FAT */
716 if (mydata->fatsize == 16)
717 newclust = 0xffff;
718 else if (mydata->fatsize == 32)
719 newclust = 0xfffffff;
720 set_fatent_value(mydata, endclust, newclust);
721
722 return gotsize;
723getit:
724 if (set_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
725 debug("error: writing cluster\n");
726 return -1;
727 }
728 gotsize += (int)actsize;
729 filesize -= actsize;
730 buffer += actsize;
731
732 if (CHECK_CLUST(curclust, mydata->fatsize)) {
733 debug("curclust: 0x%x\n", curclust);
734 debug("Invalid FAT entry\n");
735 return gotsize;
736 }
737 actsize = bytesperclust;
738 curclust = endclust = newclust;
739 } while (1);
740}
741
742/*
743 * Fill dir_entry
744 */
745static void fill_dentry(fsdata *mydata, dir_entry *dentptr,
746 const char *filename, __u32 start_cluster, __u32 size, __u8 attr)
747{
748 if (mydata->fatsize == 32)
749 dentptr->starthi =
750 cpu_to_le16((start_cluster & 0xffff0000) >> 16);
751 dentptr->start = cpu_to_le16(start_cluster & 0xffff);
752 dentptr->size = cpu_to_le32(size);
753
754 dentptr->attr = attr;
755
756 set_name(dentptr, filename);
757}
758
759/*
760 * Check whether adding a file makes the file system to
761 * exceed the size of the block device
762 * Return -1 when overflow occurs, otherwise return 0
763 */
764static int check_overflow(fsdata *mydata, __u32 clustnum, unsigned long size)
765{
766 __u32 startsect, sect_num;
767
768 if (clustnum > 0) {
769 startsect = mydata->data_begin +
770 clustnum * mydata->clust_size;
771 } else {
772 startsect = mydata->rootdir_sect;
773 }
774
775 sect_num = size / mydata->sect_size;
776 if (size % mydata->sect_size)
777 sect_num++;
778
Donggeun Kim079df722012-03-22 04:38:55 +0000779 if (startsect + sect_num > cur_part_info.start + total_sector)
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000780 return -1;
781
782 return 0;
783}
784
785/*
786 * Check if adding several entries exceed one cluster boundary
787 */
788static int is_next_clust(fsdata *mydata, dir_entry *dentptr)
789{
790 int cur_position;
791
792 cur_position = (__u8 *)dentptr - get_dentfromdir_block;
793
794 if (cur_position >= mydata->clust_size * mydata->sect_size)
795 return 1;
796 else
797 return 0;
798}
799
800static dir_entry *empty_dentptr;
801/*
802 * Find a directory entry based on filename or start cluster number
803 * If the directory entry is not found,
804 * the new position for writing a directory entry will be returned
805 */
806static dir_entry *find_directory_entry(fsdata *mydata, int startsect,
807 char *filename, dir_entry *retdent, __u32 start)
808{
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000809 __u32 curclust = (startsect - mydata->data_begin) / mydata->clust_size;
810
811 debug("get_dentfromdir: %s\n", filename);
812
813 while (1) {
814 dir_entry *dentptr;
815
816 int i;
817
818 if (get_cluster(mydata, curclust, get_dentfromdir_block,
819 mydata->clust_size * mydata->sect_size) != 0) {
820 printf("Error: reading directory block\n");
821 return NULL;
822 }
823
824 dentptr = (dir_entry *)get_dentfromdir_block;
825
826 dir_curclust = curclust;
827
828 for (i = 0; i < DIRENTSPERCLUST; i++) {
829 char s_name[14], l_name[VFAT_MAXLEN_BYTES];
830
831 l_name[0] = '\0';
832 if (dentptr->name[0] == DELETED_FLAG) {
833 dentptr++;
834 if (is_next_clust(mydata, dentptr))
835 break;
836 continue;
837 }
838 if ((dentptr->attr & ATTR_VOLUME)) {
Richard Genoudcb940c72012-12-13 03:30:10 +0000839 if (vfat_enabled &&
840 (dentptr->attr & ATTR_VFAT) &&
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000841 (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000842 get_long_file_name(mydata, curclust,
843 get_dentfromdir_block,
844 &dentptr, l_name);
845 debug("vfatname: |%s|\n", l_name);
Richard Genoudcb940c72012-12-13 03:30:10 +0000846 } else {
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000847 /* Volume label or VFAT entry */
848 dentptr++;
849 if (is_next_clust(mydata, dentptr))
850 break;
851 continue;
852 }
853 }
854 if (dentptr->name[0] == 0) {
855 debug("Dentname == NULL - %d\n", i);
856 empty_dentptr = dentptr;
857 return NULL;
858 }
859
860 get_name(dentptr, s_name);
861
862 if (strcmp(filename, s_name)
863 && strcmp(filename, l_name)) {
864 debug("Mismatch: |%s|%s|\n",
865 s_name, l_name);
866 dentptr++;
867 if (is_next_clust(mydata, dentptr))
868 break;
869 continue;
870 }
871
872 memcpy(retdent, dentptr, sizeof(dir_entry));
873
874 debug("DentName: %s", s_name);
875 debug(", start: 0x%x", START(dentptr));
876 debug(", size: 0x%x %s\n",
877 FAT2CPU32(dentptr->size),
878 (dentptr->attr & ATTR_DIR) ?
879 "(DIR)" : "");
880
881 return dentptr;
882 }
883
884 curclust = get_fatent_value(mydata, dir_curclust);
885 if ((curclust >= 0xffffff8) || (curclust >= 0xfff8)) {
886 empty_dentptr = dentptr;
887 return NULL;
888 }
889 if (CHECK_CLUST(curclust, mydata->fatsize)) {
890 debug("curclust: 0x%x\n", curclust);
891 debug("Invalid FAT entry\n");
892 return NULL;
893 }
894 }
895
896 return NULL;
897}
898
899static int do_fat_write(const char *filename, void *buffer,
900 unsigned long size)
901{
902 dir_entry *dentptr, *retdent;
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000903 __u32 startsect;
904 __u32 start_cluster;
905 boot_sector bs;
906 volume_info volinfo;
907 fsdata datablock;
908 fsdata *mydata = &datablock;
909 int cursect;
Anatolij Gustschinbf6b6af2012-03-24 23:40:56 +0100910 int ret = -1, name_len;
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000911 char l_filename[VFAT_MAXLEN_BYTES];
Anatolij Gustschin8506eb82011-12-15 03:12:14 +0000912 int write_size = size;
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000913
914 dir_curclust = 0;
915
916 if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
917 debug("error: reading boot sector\n");
918 return -1;
919 }
920
921 total_sector = bs.total_sect;
922 if (total_sector == 0)
Donggeun Kim079df722012-03-22 04:38:55 +0000923 total_sector = cur_part_info.size;
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000924
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000925 if (mydata->fatsize == 32)
926 mydata->fatlength = bs.fat32_length;
927 else
928 mydata->fatlength = bs.fat_length;
929
930 mydata->fat_sect = bs.reserved;
931
932 cursect = mydata->rootdir_sect
933 = mydata->fat_sect + mydata->fatlength * bs.fats;
Donggeun Kim627182e2011-12-20 18:34:27 +0000934 num_of_fats = bs.fats;
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000935
936 mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
937 mydata->clust_size = bs.cluster_size;
938
939 if (mydata->fatsize == 32) {
940 mydata->data_begin = mydata->rootdir_sect -
941 (mydata->clust_size * 2);
942 } else {
943 int rootdir_size;
944
945 rootdir_size = ((bs.dir_entries[1] * (int)256 +
946 bs.dir_entries[0]) *
947 sizeof(dir_entry)) /
948 mydata->sect_size;
949 mydata->data_begin = mydata->rootdir_sect +
950 rootdir_size -
951 (mydata->clust_size * 2);
952 }
953
954 mydata->fatbufnum = -1;
955 mydata->fatbuf = malloc(FATBUFSIZE);
956 if (mydata->fatbuf == NULL) {
957 debug("Error: allocating memory\n");
958 return -1;
959 }
960
961 if (disk_read(cursect,
962 (mydata->fatsize == 32) ?
963 (mydata->clust_size) :
Benoît Thébaudeau1170e632012-09-18 08:14:56 +0000964 PREFETCH_BLOCKS, do_fat_read_at_block) < 0) {
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000965 debug("Error: reading rootdir block\n");
966 goto exit;
967 }
Benoît Thébaudeau1170e632012-09-18 08:14:56 +0000968 dentptr = (dir_entry *) do_fat_read_at_block;
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000969
970 name_len = strlen(filename);
Anatolij Gustschin8506eb82011-12-15 03:12:14 +0000971 if (name_len >= VFAT_MAXLEN_BYTES)
972 name_len = VFAT_MAXLEN_BYTES - 1;
973
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000974 memcpy(l_filename, filename, name_len);
Anatolij Gustschin8506eb82011-12-15 03:12:14 +0000975 l_filename[name_len] = 0; /* terminate the string */
Donggeun Kimc30a15e2011-10-24 21:15:28 +0000976 downcase(l_filename);
977
978 startsect = mydata->rootdir_sect;
979 retdent = find_directory_entry(mydata, startsect,
980 l_filename, dentptr, 0);
981 if (retdent) {
982 /* Update file size and start_cluster in a directory entry */
983 retdent->size = cpu_to_le32(size);
984 start_cluster = FAT2CPU16(retdent->start);
985 if (mydata->fatsize == 32)
986 start_cluster |=
987 (FAT2CPU16(retdent->starthi) << 16);
988
989 ret = check_overflow(mydata, start_cluster, size);
990 if (ret) {
991 printf("Error: %ld overflow\n", size);
992 goto exit;
993 }
994
995 ret = clear_fatent(mydata, start_cluster);
996 if (ret) {
997 printf("Error: clearing FAT entries\n");
998 goto exit;
999 }
1000
1001 ret = set_contents(mydata, retdent, buffer, size);
Anatolij Gustschin8506eb82011-12-15 03:12:14 +00001002 if (ret < 0) {
Donggeun Kimc30a15e2011-10-24 21:15:28 +00001003 printf("Error: writing contents\n");
1004 goto exit;
1005 }
Anatolij Gustschin8506eb82011-12-15 03:12:14 +00001006 write_size = ret;
1007 debug("attempt to write 0x%x bytes\n", write_size);
Donggeun Kimc30a15e2011-10-24 21:15:28 +00001008
1009 /* Flush fat buffer */
1010 ret = flush_fat_buffer(mydata);
1011 if (ret) {
1012 printf("Error: flush fat buffer\n");
1013 goto exit;
1014 }
1015
1016 /* Write directory table to device */
1017 ret = set_cluster(mydata, dir_curclust,
1018 get_dentfromdir_block,
1019 mydata->clust_size * mydata->sect_size);
1020 if (ret) {
Anatolij Gustschin8506eb82011-12-15 03:12:14 +00001021 printf("Error: writing directory entry\n");
Donggeun Kimc30a15e2011-10-24 21:15:28 +00001022 goto exit;
1023 }
1024 } else {
Donggeun Kimc30a15e2011-10-24 21:15:28 +00001025 /* Set short name to set alias checksum field in dir_slot */
1026 set_name(empty_dentptr, filename);
1027 fill_dir_slot(mydata, &empty_dentptr, filename);
1028
1029 ret = start_cluster = find_empty_cluster(mydata);
1030 if (ret < 0) {
1031 printf("Error: finding empty cluster\n");
1032 goto exit;
1033 }
1034
1035 ret = check_overflow(mydata, start_cluster, size);
1036 if (ret) {
1037 printf("Error: %ld overflow\n", size);
1038 goto exit;
1039 }
1040
1041 /* Set attribute as archieve for regular file */
1042 fill_dentry(mydata, empty_dentptr, filename,
1043 start_cluster, size, 0x20);
1044
1045 ret = set_contents(mydata, empty_dentptr, buffer, size);
Anatolij Gustschin8506eb82011-12-15 03:12:14 +00001046 if (ret < 0) {
Donggeun Kimc30a15e2011-10-24 21:15:28 +00001047 printf("Error: writing contents\n");
1048 goto exit;
1049 }
Anatolij Gustschin8506eb82011-12-15 03:12:14 +00001050 write_size = ret;
1051 debug("attempt to write 0x%x bytes\n", write_size);
Donggeun Kimc30a15e2011-10-24 21:15:28 +00001052
1053 /* Flush fat buffer */
1054 ret = flush_fat_buffer(mydata);
1055 if (ret) {
1056 printf("Error: flush fat buffer\n");
1057 goto exit;
1058 }
1059
1060 /* Write directory table to device */
1061 ret = set_cluster(mydata, dir_curclust,
1062 get_dentfromdir_block,
1063 mydata->clust_size * mydata->sect_size);
1064 if (ret) {
1065 printf("Error: writing directory entry\n");
1066 goto exit;
1067 }
1068 }
1069
1070exit:
1071 free(mydata->fatbuf);
Anatolij Gustschin8506eb82011-12-15 03:12:14 +00001072 return ret < 0 ? ret : write_size;
Donggeun Kimc30a15e2011-10-24 21:15:28 +00001073}
1074
1075int file_fat_write(const char *filename, void *buffer, unsigned long maxsize)
1076{
1077 printf("writing %s\n", filename);
1078 return do_fat_write(filename, buffer, maxsize);
1079}