1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2001
4 * Raymond Lo, lo@routefree.com
5 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
6 */
7
8 /*
9 * Support for harddisk partitions.
10 *
11 * To be compatible with LinuxPPC and Apple we use the standard Apple
12 * SCSI disk partitioning scheme. For more information see:
13 * http://developer.apple.com/techpubs/mac/Devices/Devices-126.html#MARKER-14-92
14 */
15
16 #include <blk.h>
17 #include <command.h>
18 #include <memalign.h>
19 #include <vsprintf.h>
20 #include <asm/unaligned.h>
21 #include <linux/compiler.h>
22 #include "part_dos.h"
23 #include <part.h>
24
25 #define DOS_PART_DEFAULT_SECTOR 512
26
27 /* should this be configurable? It looks like it's not very common at all
28 * to use large numbers of partitions */
29 #define MAX_EXT_PARTS 256
30
is_extended(int part_type)31 static inline int is_extended(int part_type)
32 {
33 return (part_type == DOS_PART_TYPE_EXTENDED ||
34 part_type == DOS_PART_TYPE_EXTENDED_LBA ||
35 part_type == DOS_PART_TYPE_EXTENDED_LINUX);
36 }
37
get_bootable(dos_partition_t * p)38 static int get_bootable(dos_partition_t *p)
39 {
40 int ret = 0;
41
42 if (p->sys_ind == 0xef)
43 ret |= PART_EFI_SYSTEM_PARTITION;
44 if (p->boot_ind == 0x80)
45 ret |= PART_BOOTABLE;
46 return ret;
47 }
48
print_one_part(dos_partition_t * p,lbaint_t ext_part_sector,int part_num,unsigned int disksig)49 static void print_one_part(dos_partition_t *p, lbaint_t ext_part_sector,
50 int part_num, unsigned int disksig)
51 {
52 lbaint_t lba_start = ext_part_sector + get_unaligned_le32(p->start4);
53 lbaint_t lba_size = get_unaligned_le32(p->size4);
54
55 printf("%3d\t%-10" LBAFlength "u\t%-10" LBAFlength
56 "u\t%08x-%02x\t%02x%s%s\n",
57 part_num, lba_start, lba_size, disksig, part_num, p->sys_ind,
58 (is_extended(p->sys_ind) ? " Extd" : ""),
59 (get_bootable(p) ? " Boot" : ""));
60 }
61
test_block_type(unsigned char * buffer)62 static int test_block_type(unsigned char *buffer)
63 {
64 int slot;
65 struct dos_partition *p;
66 int part_count = 0;
67
68 if((buffer[DOS_PART_MAGIC_OFFSET + 0] != 0x55) ||
69 (buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) ) {
70 return (-1);
71 } /* no DOS Signature at all */
72 p = (struct dos_partition *)&buffer[DOS_PART_TBL_OFFSET];
73
74 /* Check that the boot indicators are valid and count the partitions. */
75 for (slot = 0; slot < 4; ++slot, ++p) {
76 if (p->boot_ind != 0 && p->boot_ind != 0x80)
77 break;
78 if (p->sys_ind)
79 ++part_count;
80 }
81
82 /*
83 * If the partition table is invalid or empty,
84 * check if this is a DOS PBR
85 */
86 if (slot != 4 || !part_count) {
87 if (!strncmp((char *)&buffer[DOS_PBR_FSTYPE_OFFSET],
88 "FAT", 3) ||
89 !strncmp((char *)&buffer[DOS_PBR32_FSTYPE_OFFSET],
90 "FAT32", 5))
91 return DOS_PBR; /* This is a DOS PBR and not an MBR */
92 }
93 if (slot == 4)
94 return DOS_MBR; /* This is an DOS MBR */
95
96 /* This is neither a DOS MBR nor a DOS PBR */
97 return -1;
98 }
99
part_test_dos(struct blk_desc * desc)100 static int part_test_dos(struct blk_desc *desc)
101 {
102 #ifndef CONFIG_XPL_BUILD
103 ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, mbr,
104 DIV_ROUND_UP(desc->blksz, sizeof(legacy_mbr)));
105
106 if (blk_dread(desc, 0, 1, (ulong *)mbr) != 1)
107 return -1;
108
109 if (test_block_type((unsigned char *)mbr) != DOS_MBR)
110 return -1;
111
112 if (desc->sig_type == SIG_TYPE_NONE && mbr->unique_mbr_signature) {
113 desc->sig_type = SIG_TYPE_MBR;
114 desc->mbr_sig = mbr->unique_mbr_signature;
115 }
116 #else
117 ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, desc->blksz);
118
119 if (blk_dread(desc, 0, 1, (ulong *)buffer) != 1)
120 return -1;
121
122 if (test_block_type(buffer) != DOS_MBR)
123 return -1;
124 #endif
125
126 return 0;
127 }
128
129 /* Print a partition that is relative to its Extended partition table
130 */
print_partition_extended(struct blk_desc * desc,lbaint_t ext_part_sector,lbaint_t relative,int part_num,unsigned int disksig)131 static void print_partition_extended(struct blk_desc *desc,
132 lbaint_t ext_part_sector,
133 lbaint_t relative,
134 int part_num, unsigned int disksig)
135 {
136 ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, desc->blksz);
137 dos_partition_t *pt;
138 int i;
139
140 /* set a maximum recursion level */
141 if (part_num > MAX_EXT_PARTS)
142 {
143 printf("** Nested DOS partitions detected, stopping **\n");
144 return;
145 }
146
147 if (blk_dread(desc, ext_part_sector, 1, (ulong *)buffer) != 1) {
148 printf ("** Can't read partition table on %d:" LBAFU " **\n",
149 desc->devnum, ext_part_sector);
150 return;
151 }
152 i=test_block_type(buffer);
153 if (i != DOS_MBR) {
154 printf ("bad MBR sector signature 0x%02x%02x\n",
155 buffer[DOS_PART_MAGIC_OFFSET],
156 buffer[DOS_PART_MAGIC_OFFSET + 1]);
157 return;
158 }
159
160 if (!ext_part_sector)
161 disksig = get_unaligned_le32(&buffer[DOS_PART_DISKSIG_OFFSET]);
162
163 /* Print all primary/logical partitions */
164 pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
165 for (i = 0; i < 4; i++, pt++) {
166 /*
167 * fdisk does not show the extended partitions that
168 * are not in the MBR
169 */
170
171 if ((pt->sys_ind != 0) &&
172 (ext_part_sector == 0 || !is_extended (pt->sys_ind)) ) {
173 print_one_part(pt, ext_part_sector, part_num, disksig);
174 }
175
176 /* Reverse engr the fdisk part# assignment rule! */
177 if ((ext_part_sector == 0) ||
178 (pt->sys_ind != 0 && !is_extended (pt->sys_ind)) ) {
179 part_num++;
180 }
181 }
182
183 /* Follows the extended partitions */
184 pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
185 for (i = 0; i < 4; i++, pt++) {
186 if (is_extended (pt->sys_ind)) {
187 lbaint_t lba_start
188 = get_unaligned_le32 (pt->start4) + relative;
189
190 print_partition_extended(desc, lba_start,
191 !ext_part_sector ? lba_start :
192 relative, part_num, disksig);
193 }
194 }
195
196 return;
197 }
198
199 /* Print a partition that is relative to its Extended partition table
200 */
part_get_info_extended(struct blk_desc * desc,lbaint_t ext_part_sector,lbaint_t relative,int part_num,int which_part,struct disk_partition * info,uint disksig)201 static int part_get_info_extended(struct blk_desc *desc,
202 lbaint_t ext_part_sector, lbaint_t relative,
203 int part_num, int which_part,
204 struct disk_partition *info, uint disksig)
205 {
206 ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, desc->blksz);
207 struct disk_partition wdinfo = { 0 };
208 dos_partition_t *pt;
209 int i, ret;
210 int dos_type;
211
212 /* set a maximum recursion level */
213 if (part_num > MAX_EXT_PARTS)
214 {
215 printf("** Nested DOS partitions detected, stopping **\n");
216 return -1;
217 }
218
219 if (blk_dread(desc, ext_part_sector, 1, (ulong *)buffer) != 1) {
220 printf ("** Can't read partition table on %d:" LBAFU " **\n",
221 desc->devnum, ext_part_sector);
222 return -1;
223 }
224 if (buffer[DOS_PART_MAGIC_OFFSET] != 0x55 ||
225 buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) {
226 printf ("bad MBR sector signature 0x%02x%02x\n",
227 buffer[DOS_PART_MAGIC_OFFSET],
228 buffer[DOS_PART_MAGIC_OFFSET + 1]);
229 return -1;
230 }
231
232 if (CONFIG_IS_ENABLED(PARTITION_UUIDS) && !ext_part_sector)
233 disksig = get_unaligned_le32(&buffer[DOS_PART_DISKSIG_OFFSET]);
234
235 ret = part_get_info_whole_disk(desc, &wdinfo);
236 if (ret)
237 return ret;
238
239 /* Print all primary/logical partitions */
240 pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
241 for (i = 0; i < 4; i++, pt++) {
242 /*
243 * fdisk does not show the extended partitions that
244 * are not in the MBR
245 */
246 if (((pt->boot_ind & ~0x80) == 0) &&
247 (pt->sys_ind != 0) &&
248 (part_num == which_part) &&
249 (ext_part_sector == 0 || is_extended(pt->sys_ind) == 0)) {
250 if (wdinfo.blksz > DOS_PART_DEFAULT_SECTOR)
251 info->blksz = wdinfo.blksz;
252 else
253 info->blksz = DOS_PART_DEFAULT_SECTOR;
254 info->start = (lbaint_t)(ext_part_sector +
255 get_unaligned_le32(pt->start4));
256 info->size = (lbaint_t)get_unaligned_le32(pt->size4);
257 part_set_generic_name(desc, part_num,
258 (char *)info->name);
259 /* sprintf(info->type, "%d, pt->sys_ind); */
260 strcpy((char *)info->type, "U-Boot");
261 info->bootable = get_bootable(pt);
262 if (CONFIG_IS_ENABLED(PARTITION_UUIDS)) {
263 char str[12];
264
265 sprintf(str, "%08x-%02x", disksig, part_num);
266 disk_partition_set_uuid(info, str);
267 }
268 info->sys_ind = pt->sys_ind;
269 return 0;
270 }
271
272 /* Reverse engr the fdisk part# assignment rule! */
273 if ((ext_part_sector == 0) ||
274 (pt->sys_ind != 0 && !is_extended (pt->sys_ind)) ) {
275 part_num++;
276 }
277 }
278
279 /* Follows the extended partitions */
280 pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
281 for (i = 0; i < 4; i++, pt++) {
282 if (is_extended (pt->sys_ind)) {
283 lbaint_t lba_start
284 = get_unaligned_le32 (pt->start4) + relative;
285
286 return part_get_info_extended(desc, lba_start,
287 ext_part_sector == 0 ? lba_start : relative,
288 part_num, which_part, info, disksig);
289 }
290 }
291
292 /* Check for DOS PBR if no partition is found */
293 dos_type = test_block_type(buffer);
294
295 if (dos_type == DOS_PBR) {
296 info->start = 0;
297 info->size = desc->lba;
298 if (wdinfo.blksz > DOS_PART_DEFAULT_SECTOR)
299 info->blksz = wdinfo.blksz;
300 else
301 info->blksz = DOS_PART_DEFAULT_SECTOR;
302 info->bootable = 0;
303 strcpy((char *)info->type, "U-Boot");
304 disk_partition_clr_uuid(info);
305 return 0;
306 }
307
308 return -1;
309 }
310
part_print_dos(struct blk_desc * desc)311 static void __maybe_unused part_print_dos(struct blk_desc *desc)
312 {
313 printf("Part\tStart Sector\tNum Sectors\tUUID\t\tType\n");
314 print_partition_extended(desc, 0, 0, 1, 0);
315 }
316
part_get_info_dos(struct blk_desc * desc,int part,struct disk_partition * info)317 static int __maybe_unused part_get_info_dos(struct blk_desc *desc, int part,
318 struct disk_partition *info)
319 {
320 return part_get_info_extended(desc, 0, 0, 1, part, info, 0);
321 }
322
is_valid_dos_buf(void * buf)323 int is_valid_dos_buf(void *buf)
324 {
325 return test_block_type(buf) == DOS_MBR ? 0 : -1;
326 }
327
328 #if IS_ENABLED(CONFIG_CMD_MBR)
lba_to_chs(lbaint_t lba,unsigned char * rc,unsigned char * rh,unsigned char * rs)329 static void lba_to_chs(lbaint_t lba, unsigned char *rc, unsigned char *rh,
330 unsigned char *rs)
331 {
332 unsigned int c, h, s;
333 /* use fixed CHS geometry */
334 unsigned int sectpertrack = 63;
335 unsigned int heads = 255;
336
337 c = (lba + 1) / sectpertrack / heads;
338 h = (lba + 1) / sectpertrack - c * heads;
339 s = (lba + 1) - (c * heads + h) * sectpertrack;
340
341 if (c > 1023) {
342 c = 1023;
343 h = 254;
344 s = 63;
345 }
346
347 *rc = c & 0xff;
348 *rh = h;
349 *rs = s + ((c & 0x300) >> 2);
350 }
351
mbr_fill_pt_entry(dos_partition_t * pt,lbaint_t start,lbaint_t relative,lbaint_t size,uchar sys_ind,bool bootable)352 static void mbr_fill_pt_entry(dos_partition_t *pt, lbaint_t start,
353 lbaint_t relative, lbaint_t size, uchar sys_ind, bool bootable)
354 {
355 pt->boot_ind = bootable ? 0x80 : 0x00;
356 pt->sys_ind = sys_ind;
357 lba_to_chs(start, &pt->cyl, &pt->head, &pt->sector);
358 lba_to_chs(start + size - 1, &pt->end_cyl, &pt->end_head, &pt->end_sector);
359 put_unaligned_le32(relative, &pt->start4);
360 put_unaligned_le32(size, &pt->size4);
361 }
362
write_mbr_partitions(struct blk_desc * dev,struct disk_partition * p,int count,unsigned int disksig)363 int write_mbr_partitions(struct blk_desc *dev,
364 struct disk_partition *p, int count, unsigned int disksig)
365 {
366 ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev->blksz);
367 lbaint_t ext_part_start = 0, ext_part_size = 0, ext_part_sect = 0;
368 dos_partition_t *pt;
369 int i;
370
371 memset(buffer, 0, dev->blksz);
372 buffer[DOS_PART_MAGIC_OFFSET] = 0x55;
373 buffer[DOS_PART_MAGIC_OFFSET + 1] = 0xaa;
374 put_unaligned_le32(disksig, &buffer[DOS_PART_DISKSIG_OFFSET]);
375 pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
376
377 /* create all primary partitions */
378 for (i = 0; i < 4 && i < count; i++, pt++) {
379 mbr_fill_pt_entry(pt, p[i].start, p[i].start, p[i].size,
380 p[i].sys_ind, p[i].bootable);
381 if (is_extended(p[i].sys_ind)) {
382 ext_part_start = p[i].start;
383 ext_part_size = p[i].size;
384 ext_part_sect = p[i].start;
385 }
386 }
387
388 if (i < count && !ext_part_start) {
389 printf("%s: extended partition is needed for more than 4 partitions\n",
390 __func__);
391 return -1;
392 }
393
394 /* write MBR */
395 if (blk_dwrite(dev, 0, 1, buffer) != 1) {
396 printf("%s: failed writing 'MBR' (1 blks at 0x0)\n",
397 __func__);
398 return -1;
399 }
400
401 /* create extended volumes */
402 for (; i < count; i++) {
403 lbaint_t next_ebr = 0;
404
405 memset(buffer, 0, dev->blksz);
406 buffer[DOS_PART_MAGIC_OFFSET] = 0x55;
407 buffer[DOS_PART_MAGIC_OFFSET + 1] = 0xaa;
408 pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
409
410 mbr_fill_pt_entry(pt, p[i].start, p[i].start - ext_part_sect,
411 p[i].size, p[i].sys_ind, p[i].bootable);
412
413 if (i + 1 < count) {
414 pt++;
415 next_ebr = p[i].start + p[i].size;
416 mbr_fill_pt_entry(pt, next_ebr,
417 next_ebr - ext_part_start,
418 p[i+1].start + p[i+1].size - next_ebr,
419 DOS_PART_TYPE_EXTENDED, 0);
420 }
421
422 /* write EBR */
423 if (blk_dwrite(dev, ext_part_sect, 1, buffer) != 1) {
424 printf("%s: failed writing 'EBR' (1 blks at 0x" LBAF ")\n",
425 __func__, ext_part_sect);
426 return -1;
427 }
428 ext_part_sect = next_ebr;
429 }
430
431 /* Update the partition table entries*/
432 part_init(dev);
433
434 return 0;
435 }
436
layout_mbr_partitions(struct disk_partition * p,int count,lbaint_t total_sectors)437 int layout_mbr_partitions(struct disk_partition *p, int count,
438 lbaint_t total_sectors)
439 {
440 struct disk_partition *ext = NULL;
441 int i, j;
442 lbaint_t ext_vol_start;
443
444 /* calculate primary partitions start and size if needed */
445 if (!p[0].start)
446 p[0].start = DOS_PART_DEFAULT_GAP;
447 for (i = 0; i < 4 && i < count; i++) {
448 if (!p[i].start)
449 p[i].start = p[i - 1].start + p[i - 1].size;
450 if (!p[i].size) {
451 lbaint_t end = total_sectors;
452 lbaint_t allocated = 0;
453
454 for (j = i + 1; j < 4 && j < count; j++) {
455 if (p[j].start) {
456 end = p[j].start;
457 break;
458 }
459 allocated += p[j].size;
460 }
461 p[i].size = end - allocated - p[i].start;
462 }
463 if (p[i].sys_ind == 0x05)
464 ext = &p[i];
465 }
466
467 if (count <= 4)
468 return 0;
469
470 if (!ext) {
471 log_err("extended partition is needed for more than 4 partitions\n");
472 return -EINVAL;
473 }
474
475 /* calculate extended volumes start and size if needed */
476 ext_vol_start = ext->start;
477 for (i = 4; i < count; i++) {
478 if (!p[i].start)
479 p[i].start = ext_vol_start + DOS_PART_DEFAULT_GAP;
480 if (!p[i].size) {
481 lbaint_t end = ext->start + ext->size;
482 lbaint_t allocated = 0;
483
484 for (j = i + 1; j < count; j++) {
485 if (p[j].start) {
486 end = p[j].start - DOS_PART_DEFAULT_GAP;
487 break;
488 }
489 allocated += p[j].size + DOS_PART_DEFAULT_GAP;
490 }
491 p[i].size = end - allocated - p[i].start;
492 }
493 ext_vol_start = p[i].start + p[i].size;
494 }
495
496 return 0;
497 }
498 #endif
499
write_mbr_sector(struct blk_desc * desc,void * buf)500 int write_mbr_sector(struct blk_desc *desc, void *buf)
501 {
502 if (is_valid_dos_buf(buf))
503 return -1;
504
505 /* write MBR */
506 if (blk_dwrite(desc, 0, 1, buf) != 1) {
507 printf("%s: failed writing '%s' (1 blks at 0x0)\n",
508 __func__, "MBR");
509 return 1;
510 }
511
512 /* Update the partition table entries*/
513 part_init(desc);
514
515 return 0;
516 }
517
518 U_BOOT_PART_TYPE(dos) = {
519 .name = "DOS",
520 .part_type = PART_TYPE_DOS,
521 .max_entries = DOS_ENTRY_NUMBERS,
522 .get_info = part_get_info_ptr(part_get_info_dos),
523 .print = part_print_ptr(part_print_dos),
524 .test = part_test_dos,
525 };
526