disk/part_efi.c

   1 /*
   2  * Copyright (C) 2008 RuggedCom, Inc.
   3  * Richard Retanubun <RichardRetanubun@RuggedCom.com>
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 /*
  25  * Problems with CONFIG_SYS_64BIT_LBA:
  26  *
  27  * struct disk_partition.start in include/part.h is sized as ulong.
  28  * When CONFIG_SYS_64BIT_LBA is activated, lbaint_t changes from ulong to uint64_t.
  29  * For now, it is cast back to ulong at assignment.
  30  *
  31  * This limits the maximum size of addressable storage to < 2 Terra Bytes
  32  */
  33 #include <common.h>
  34 #include <command.h>
  35 #include <ide.h>
  36 #include <malloc.h>
  37 #include <part_efi.h>
  38 #include <linux/ctype.h>
  39
  40 DECLARE_GLOBAL_DATA_PTR;
  41
  42 #if defined(CONFIG_CMD_IDE) || \
  43     defined(CONFIG_CMD_SATA) || \
  44     defined(CONFIG_CMD_SCSI) || \
  45     defined(CONFIG_CMD_USB) || \
  46     defined(CONFIG_MMC) || \
  47     defined(CONFIG_SYSTEMACE)
  48
  49 /**
  50  * efi_crc32() - EFI version of crc32 function
  51  * @buf: buffer to calculate crc32 of
  52  * @len - length of buf
  53  *
  54  * Description: Returns EFI-style CRC32 value for @buf
  55  */
  56 static inline u32 efi_crc32(const void *buf, u32 len)
  57 {
  58         return crc32(0, buf, len);
  59 }
  60
  61 /*
  62  * Private function prototypes
  63  */
  64
  65 static int pmbr_part_valid(struct partition *part);
  66 static int is_pmbr_valid(legacy_mbr * mbr);
  67 static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba,
  68                                 gpt_header * pgpt_head, gpt_entry ** pgpt_pte);
  69 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
  70                                 gpt_header * pgpt_head);
  71 static int is_pte_valid(gpt_entry * pte);
  72
  73 static char *print_efiname(gpt_entry *pte)
  74 {
  75         static char name[PARTNAME_SZ + 1];
  76         int i;
  77         for (i = 0; i < PARTNAME_SZ; i++) {
  78                 u8 c;
  79                 c = pte->partition_name[i] & 0xff;
  80                 c = (c && !isprint(c)) ? '.' : c;
  81                 name[i] = c;
  82         }
  83         name[PARTNAME_SZ] = 0;
  84         return name;
  85 }
  86
  87 static void uuid_string(unsigned char *uuid, char *str)
  88 {
  89         static const u8 le[16] = {3, 2, 1, 0, 5, 4, 7, 6, 8, 9, 10, 11,
  90                                   12, 13, 14, 15};
  91         int i;
  92
  93         for (i = 0; i < 16; i++) {
  94                 sprintf(str, "%02x", uuid[le[i]]);
  95                 str += 2;
  96                 switch (i) {
  97                 case 3:
  98                 case 5:
  99                 case 7:
 100                 case 9:
 101                         *str++ = '-';
 102                         break;
 103                 }
 104         }
 105 }
 106
 107 static efi_guid_t system_guid = PARTITION_SYSTEM_GUID;
 108
 109 static inline int is_bootable(gpt_entry *p)
 110 {
 111         return p->attributes.fields.legacy_bios_bootable ||
 112                 !memcmp(&(p->partition_type_guid), &system_guid,
 113                         sizeof(efi_guid_t));
 114 }
 115
 116 #ifdef CONFIG_EFI_PARTITION
 117 /*
 118  * Public Functions (include/part.h)
 119  */
 120
 121 void print_part_efi(block_dev_desc_t * dev_desc)
 122 {
 123         ALLOC_CACHE_ALIGN_BUFFER(gpt_header, gpt_head, 1);
 124         gpt_entry *gpt_pte = NULL;
 125         int i = 0;
 126         char uuid[37];
 127
 128         if (!dev_desc) {
 129                 printf("%s: Invalid Argument(s)\n", __func__);
 130                 return;
 131         }
 132         /* This function validates AND fills in the GPT header and PTE */
 133         if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
 134                          gpt_head, &gpt_pte) != 1) {
 135                 printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
 136                 return;
 137         }
 138
 139         debug("%s: gpt-entry at %p\n", __func__, gpt_pte);
 140
 141         printf("Part\tStart LBA\tEnd LBA\t\tName\n");
 142         printf("\tAttributes\n");
 143         printf("\tType UUID\n");
 144         printf("\tPartition UUID\n");
 145
 146         for (i = 0; i < le32_to_cpu(gpt_head->num_partition_entries); i++) {
 147                 /* Stop at the first non valid PTE */
 148                 if (!is_pte_valid(&gpt_pte[i]))
 149                         break;
 150
 151                 printf("%3d\t0x%08llx\t0x%08llx\t\"%s\"\n", (i + 1),
 152                         le64_to_cpu(gpt_pte[i].starting_lba),
 153                         le64_to_cpu(gpt_pte[i].ending_lba),
 154                         print_efiname(&gpt_pte[i]));
 155                 printf("\tattrs:\t0x%016llx\n", gpt_pte[i].attributes.raw);
 156                 uuid_string(gpt_pte[i].partition_type_guid.b, uuid);
 157                 printf("\ttype:\t%s\n", uuid);
 158                 uuid_string(gpt_pte[i].unique_partition_guid.b, uuid);
 159                 printf("\tuuid:\t%s\n", uuid);
 160         }
 161
 162         /* Remember to free pte */
 163         free(gpt_pte);
 164         return;
 165 }
 166
 167 int get_partition_info_efi(block_dev_desc_t * dev_desc, int part,
 168                                 disk_partition_t * info)
 169 {
 170         ALLOC_CACHE_ALIGN_BUFFER(gpt_header, gpt_head, 1);
 171         gpt_entry *gpt_pte = NULL;
 172
 173         /* "part" argument must be at least 1 */
 174         if (!dev_desc || !info || part < 1) {
 175                 printf("%s: Invalid Argument(s)\n", __func__);
 176                 return -1;
 177         }
 178
 179         /* This function validates AND fills in the GPT header and PTE */
 180         if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
 181                         gpt_head, &gpt_pte) != 1) {
 182                 printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
 183                 return -1;
 184         }
 185
 186         if (part > le32_to_cpu(gpt_head->num_partition_entries) ||
 187             !is_pte_valid(&gpt_pte[part - 1])) {
 188                 printf("%s: *** ERROR: Invalid partition number %d ***\n",
 189                         __func__, part);
 190                 return -1;
 191         }
 192
 193         /* The ulong casting limits the maximum disk size to 2 TB */
 194         info->start = (u64)le64_to_cpu(gpt_pte[part - 1].starting_lba);
 195         /* The ending LBA is inclusive, to calculate size, add 1 to it */
 196         info->size = ((u64)le64_to_cpu(gpt_pte[part - 1].ending_lba) + 1)
 197                      - info->start;
 198         info->blksz = GPT_BLOCK_SIZE;
 199
 200         sprintf((char *)info->name, "%s",
 201                         print_efiname(&gpt_pte[part - 1]));
 202         sprintf((char *)info->type, "U-Boot");
 203         info->bootable = is_bootable(&gpt_pte[part - 1]);
 204 #ifdef CONFIG_PARTITION_UUIDS
 205         uuid_string(gpt_pte[part - 1].unique_partition_guid.b, info->uuid);
 206 #endif
 207
 208         debug("%s: start 0x%lX, size 0x%lX, name %s", __func__,
 209                 info->start, info->size, info->name);
 210
 211         /* Remember to free pte */
 212         free(gpt_pte);
 213         return 0;
 214 }
 215
 216 int test_part_efi(block_dev_desc_t * dev_desc)
 217 {
 218         ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, legacymbr, 1);
 219
 220         /* Read legacy MBR from block 0 and validate it */
 221         if ((dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *)legacymbr) != 1)
 222                 || (is_pmbr_valid(legacymbr) != 1)) {
 223                 return -1;
 224         }
 225         return 0;
 226 }
 227
 228 /**
 229  * set_protective_mbr(): Set the EFI protective MBR
 230  * @param dev_desc - block device descriptor
 231  *
 232  * @return - zero on success, otherwise error
 233  */
 234 static int set_protective_mbr(block_dev_desc_t *dev_desc)
 235 {
 236         legacy_mbr *p_mbr;
 237
 238         /* Setup the Protective MBR */
 239         p_mbr = calloc(1, sizeof(p_mbr));
 240         if (p_mbr == NULL) {
 241                 printf("%s: calloc failed!\n", __func__);
 242                 return -1;
 243         }
 244         /* Append signature */
 245         p_mbr->signature = MSDOS_MBR_SIGNATURE;
 246         p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT;
 247         p_mbr->partition_record[0].start_sect = 1;
 248         p_mbr->partition_record[0].nr_sects = (u32) dev_desc->lba;
 249
 250         /* Write MBR sector to the MMC device */
 251         if (dev_desc->block_write(dev_desc->dev, 0, 1, p_mbr) != 1) {
 252                 printf("** Can't write to device %d **\n",
 253                         dev_desc->dev);
 254                 free(p_mbr);
 255                 return -1;
 256         }
 257
 258         free(p_mbr);
 259         return 0;
 260 }
 261
 262 /**
 263  * string_uuid(); Convert UUID stored as string to bytes
 264  *
 265  * @param uuid - UUID represented as string
 266  * @param dst - GUID buffer
 267  *
 268  * @return return 0 on successful conversion
 269  */
 270 static int string_uuid(char *uuid, u8 *dst)
 271 {
 272         efi_guid_t guid;
 273         u16 b, c, d;
 274         u64 e;
 275         u32 a;
 276         u8 *p;
 277         u8 i;
 278
 279         const u8 uuid_str_len = 36;
 280
 281         /* The UUID is written in text: */
 282         /* 1        9    14   19   24 */
 283         /* xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx */
 284
 285         debug("%s: uuid: %s\n", __func__, uuid);
 286
 287         if (strlen(uuid) != uuid_str_len)
 288                 return -1;
 289
 290         for (i = 0; i < uuid_str_len; i++) {
 291                 if ((i == 8) || (i == 13) || (i == 18) || (i == 23)) {
 292                         if (uuid[i] != '-')
 293                                 return -1;
 294                 } else {
 295                         if (!isxdigit(uuid[i]))
 296                                 return -1;
 297                 }
 298         }
 299
 300         a = (u32)simple_strtoul(uuid, NULL, 16);
 301         b = (u16)simple_strtoul(uuid + 9, NULL, 16);
 302         c = (u16)simple_strtoul(uuid + 14, NULL, 16);
 303         d = (u16)simple_strtoul(uuid + 19, NULL, 16);
 304         e = (u64)simple_strtoull(uuid + 24, NULL, 16);
 305
 306         p = (u8 *) &e;
 307         guid = EFI_GUID(a, b, c, d >> 8, d & 0xFF,
 308                         *(p + 5), *(p + 4), *(p + 3),
 309                         *(p + 2), *(p + 1) , *p);
 310
 311         memcpy(dst, guid.b, sizeof(efi_guid_t));
 312
 313         return 0;
 314 }
 315
 316 int write_gpt_table(block_dev_desc_t *dev_desc,
 317                 gpt_header *gpt_h, gpt_entry *gpt_e)
 318 {
 319         const int pte_blk_num = (gpt_h->num_partition_entries
 320                 * sizeof(gpt_entry)) / dev_desc->blksz;
 321
 322         u32 calc_crc32;
 323         u64 val;
 324
 325         debug("max lba: %x\n", (u32) dev_desc->lba);
 326         /* Setup the Protective MBR */
 327         if (set_protective_mbr(dev_desc) < 0)
 328                 goto err;
 329
 330         /* Generate CRC for the Primary GPT Header */
 331         calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
 332                               le32_to_cpu(gpt_h->num_partition_entries) *
 333                               le32_to_cpu(gpt_h->sizeof_partition_entry));
 334         gpt_h->partition_entry_array_crc32 = cpu_to_le32(calc_crc32);
 335
 336         calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
 337                               le32_to_cpu(gpt_h->header_size));
 338         gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
 339
 340         /* Write the First GPT to the block right after the Legacy MBR */
 341         if (dev_desc->block_write(dev_desc->dev, 1, 1, gpt_h) != 1)
 342                 goto err;
 343
 344         if (dev_desc->block_write(dev_desc->dev, 2, pte_blk_num, gpt_e)
 345             != pte_blk_num)
 346                 goto err;
 347
 348         /* recalculate the values for the Second GPT Header */
 349         val = le64_to_cpu(gpt_h->my_lba);
 350         gpt_h->my_lba = gpt_h->alternate_lba;
 351         gpt_h->alternate_lba = cpu_to_le64(val);
 352         gpt_h->header_crc32 = 0;
 353
 354         calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
 355                               le32_to_cpu(gpt_h->header_size));
 356         gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
 357
 358         if (dev_desc->block_write(dev_desc->dev,
 359                                   le32_to_cpu(gpt_h->last_usable_lba + 1),
 360                                   pte_blk_num, gpt_e) != pte_blk_num)
 361                 goto err;
 362
 363         if (dev_desc->block_write(dev_desc->dev,
 364                                   le32_to_cpu(gpt_h->my_lba), 1, gpt_h) != 1)
 365                 goto err;
 366
 367         debug("GPT successfully written to block device!\n");
 368         return 0;
 369
 370  err:
 371         printf("** Can't write to device %d **\n", dev_desc->dev);
 372         return -1;
 373 }
 374
 375 int gpt_fill_pte(gpt_header *gpt_h, gpt_entry *gpt_e,
 376                 disk_partition_t *partitions, int parts)
 377 {
 378         u32 offset = (u32)le32_to_cpu(gpt_h->first_usable_lba);
 379         ulong start;
 380         int i, k;
 381         size_t name_len;
 382 #ifdef CONFIG_PARTITION_UUIDS
 383         char *str_uuid;
 384 #endif
 385
 386         for (i = 0; i < parts; i++) {
 387                 /* partition starting lba */
 388                 start = partitions[i].start;
 389                 if (start && (start < offset)) {
 390                         printf("Partition overlap\n");
 391                         return -1;
 392                 }
 393                 if (start) {
 394                         gpt_e[i].starting_lba = cpu_to_le64(start);
 395                         offset = start + partitions[i].size;
 396                 } else {
 397                         gpt_e[i].starting_lba = cpu_to_le64(offset);
 398                         offset += partitions[i].size;
 399                 }
 400                 if (offset >= gpt_h->last_usable_lba) {
 401                         printf("Partitions layout exceds disk size\n");
 402                         return -1;
 403                 }
 404                 /* partition ending lba */
 405                 if ((i == parts - 1) && (partitions[i].size == 0))
 406                         /* extend the last partition to maximuim */
 407                         gpt_e[i].ending_lba = gpt_h->last_usable_lba;
 408                 else
 409                         gpt_e[i].ending_lba = cpu_to_le64(offset - 1);
 410
 411                 /* partition type GUID */
 412                 memcpy(gpt_e[i].partition_type_guid.b,
 413                         &PARTITION_BASIC_DATA_GUID, 16);
 414
 415 #ifdef CONFIG_PARTITION_UUIDS
 416                 str_uuid = partitions[i].uuid;
 417                 if (string_uuid(str_uuid, gpt_e[i].unique_partition_guid.b)) {
 418                         printf("Partition no. %d: invalid guid: %s\n",
 419                                 i, str_uuid);
 420                         return -1;
 421                 }
 422 #endif
 423
 424                 /* partition attributes */
 425                 memset(&gpt_e[i].attributes, 0,
 426                        sizeof(gpt_entry_attributes));
 427
 428                 /* partition name */
 429                 name_len = sizeof(gpt_e[i].partition_name)
 430                         / sizeof(efi_char16_t);
 431                 for (k = 0; k < name_len; k++)
 432                         gpt_e[i].partition_name[k] =
 433                                 (efi_char16_t)(partitions[i].name[k]);
 434
 435                 debug("%s: name: %s offset[%d]: 0x%x size[%d]: 0x%lx\n",
 436                       __func__, partitions[i].name, i,
 437                       offset, i, partitions[i].size);
 438         }
 439
 440         return 0;
 441 }
 442
 443 int gpt_fill_header(block_dev_desc_t *dev_desc, gpt_header *gpt_h,
 444                 char *str_guid, int parts_count)
 445 {
 446         gpt_h->signature = cpu_to_le64(GPT_HEADER_SIGNATURE);
 447         gpt_h->revision = cpu_to_le32(GPT_HEADER_REVISION_V1);
 448         gpt_h->header_size = cpu_to_le32(sizeof(gpt_header));
 449         gpt_h->my_lba = cpu_to_le64(1);
 450         gpt_h->alternate_lba = cpu_to_le64(dev_desc->lba - 1);
 451         gpt_h->first_usable_lba = cpu_to_le64(34);
 452         gpt_h->last_usable_lba = cpu_to_le64(dev_desc->lba - 34);
 453         gpt_h->partition_entry_lba = cpu_to_le64(2);
 454         gpt_h->num_partition_entries = cpu_to_le32(GPT_ENTRY_NUMBERS);
 455         gpt_h->sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry));
 456         gpt_h->header_crc32 = 0;
 457         gpt_h->partition_entry_array_crc32 = 0;
 458
 459         if (string_uuid(str_guid, gpt_h->disk_guid.b))
 460                 return -1;
 461
 462         return 0;
 463 }
 464
 465 int gpt_restore(block_dev_desc_t *dev_desc, char *str_disk_guid,
 466                 disk_partition_t *partitions, int parts_count)
 467 {
 468         int ret;
 469
 470         gpt_header *gpt_h = calloc(1, sizeof(gpt_header));
 471         if (gpt_h == NULL) {
 472                 printf("%s: calloc failed!\n", __func__);
 473                 return -1;
 474         }
 475
 476         gpt_entry *gpt_e = calloc(GPT_ENTRY_NUMBERS, sizeof(gpt_entry));
 477         if (gpt_e == NULL) {
 478                 printf("%s: calloc failed!\n", __func__);
 479                 free(gpt_h);
 480                 return -1;
 481         }
 482
 483         /* Generate Primary GPT header (LBA1) */
 484         ret = gpt_fill_header(dev_desc, gpt_h, str_disk_guid, parts_count);
 485         if (ret)
 486                 goto err;
 487
 488         /* Generate partition entries */
 489         ret = gpt_fill_pte(gpt_h, gpt_e, partitions, parts_count);
 490         if (ret)
 491                 goto err;
 492
 493         /* Write GPT partition table */
 494         ret = write_gpt_table(dev_desc, gpt_h, gpt_e);
 495
 496 err:
 497         free(gpt_e);
 498         free(gpt_h);
 499         return ret;
 500 }
 501 #endif
 502
 503 /*
 504  * Private functions
 505  */
 506 /*
 507  * pmbr_part_valid(): Check for EFI partition signature
 508  *
 509  * Returns: 1 if EFI GPT partition type is found.
 510  */
 511 static int pmbr_part_valid(struct partition *part)
 512 {
 513         if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
 514                 le32_to_cpu(part->start_sect) == 1UL) {
 515                 return 1;
 516         }
 517
 518         return 0;
 519 }
 520
 521 /*
 522  * is_pmbr_valid(): test Protective MBR for validity
 523  *
 524  * Returns: 1 if PMBR is valid, 0 otherwise.
 525  * Validity depends on two things:
 526  *  1) MSDOS signature is in the last two bytes of the MBR
 527  *  2) One partition of type 0xEE is found, checked by pmbr_part_valid()
 528  */
 529 static int is_pmbr_valid(legacy_mbr * mbr)
 530 {
 531         int i = 0;
 532
 533         if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
 534                 return 0;
 535
 536         for (i = 0; i < 4; i++) {
 537                 if (pmbr_part_valid(&mbr->partition_record[i])) {
 538                         return 1;
 539                 }
 540         }
 541         return 0;
 542 }
 543
 544 /**
 545  * is_gpt_valid() - tests one GPT header and PTEs for validity
 546  *
 547  * lba is the logical block address of the GPT header to test
 548  * gpt is a GPT header ptr, filled on return.
 549  * ptes is a PTEs ptr, filled on return.
 550  *
 551  * Description: returns 1 if valid,  0 on error.
 552  * If valid, returns pointers to PTEs.
 553  */
 554 static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba,
 555                         gpt_header * pgpt_head, gpt_entry ** pgpt_pte)
 556 {
 557         u32 crc32_backup = 0;
 558         u32 calc_crc32;
 559         unsigned long long lastlba;
 560
 561         if (!dev_desc || !pgpt_head) {
 562                 printf("%s: Invalid Argument(s)\n", __func__);
 563                 return 0;
 564         }
 565
 566         /* Read GPT Header from device */
 567         if (dev_desc->block_read(dev_desc->dev, lba, 1, pgpt_head) != 1) {
 568                 printf("*** ERROR: Can't read GPT header ***\n");
 569                 return 0;
 570         }
 571
 572         /* Check the GPT header signature */
 573         if (le64_to_cpu(pgpt_head->signature) != GPT_HEADER_SIGNATURE) {
 574                 printf("GUID Partition Table Header signature is wrong:"
 575                         "0x%llX != 0x%llX\n",
 576                         le64_to_cpu(pgpt_head->signature),
 577                         GPT_HEADER_SIGNATURE);
 578                 return 0;
 579         }
 580
 581         /* Check the GUID Partition Table CRC */
 582         memcpy(&crc32_backup, &pgpt_head->header_crc32, sizeof(crc32_backup));
 583         memset(&pgpt_head->header_crc32, 0, sizeof(pgpt_head->header_crc32));
 584
 585         calc_crc32 = efi_crc32((const unsigned char *)pgpt_head,
 586                 le32_to_cpu(pgpt_head->header_size));
 587
 588         memcpy(&pgpt_head->header_crc32, &crc32_backup, sizeof(crc32_backup));
 589
 590         if (calc_crc32 != le32_to_cpu(crc32_backup)) {
 591                 printf("GUID Partition Table Header CRC is wrong:"
 592                         "0x%x != 0x%x\n",
 593                        le32_to_cpu(crc32_backup), calc_crc32);
 594                 return 0;
 595         }
 596
 597         /* Check that the my_lba entry points to the LBA that contains the GPT */
 598         if (le64_to_cpu(pgpt_head->my_lba) != lba) {
 599                 printf("GPT: my_lba incorrect: %llX != %llX\n",
 600                         le64_to_cpu(pgpt_head->my_lba),
 601                         lba);
 602                 return 0;
 603         }
 604
 605         /* Check the first_usable_lba and last_usable_lba are within the disk. */
 606         lastlba = (unsigned long long)dev_desc->lba;
 607         if (le64_to_cpu(pgpt_head->first_usable_lba) > lastlba) {
 608                 printf("GPT: first_usable_lba incorrect: %llX > %llX\n",
 609                         le64_to_cpu(pgpt_head->first_usable_lba), lastlba);
 610                 return 0;
 611         }
 612         if (le64_to_cpu(pgpt_head->last_usable_lba) > lastlba) {
 613                 printf("GPT: last_usable_lba incorrect: %llX > %llX\n",
 614                         (u64) le64_to_cpu(pgpt_head->last_usable_lba), lastlba);
 615                 return 0;
 616         }
 617
 618         debug("GPT: first_usable_lba: %llX last_usable_lba %llX last lba %llX\n",
 619                 le64_to_cpu(pgpt_head->first_usable_lba),
 620                 le64_to_cpu(pgpt_head->last_usable_lba), lastlba);
 621
 622         /* Read and allocate Partition Table Entries */
 623         *pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head);
 624         if (*pgpt_pte == NULL) {
 625                 printf("GPT: Failed to allocate memory for PTE\n");
 626                 return 0;
 627         }
 628
 629         /* Check the GUID Partition Table Entry Array CRC */
 630         calc_crc32 = efi_crc32((const unsigned char *)*pgpt_pte,
 631                 le32_to_cpu(pgpt_head->num_partition_entries) *
 632                 le32_to_cpu(pgpt_head->sizeof_partition_entry));
 633
 634         if (calc_crc32 != le32_to_cpu(pgpt_head->partition_entry_array_crc32)) {
 635                 printf("GUID Partition Table Entry Array CRC is wrong:"
 636                         "0x%x != 0x%x\n",
 637                         le32_to_cpu(pgpt_head->partition_entry_array_crc32),
 638                         calc_crc32);
 639
 640                 free(*pgpt_pte);
 641                 return 0;
 642         }
 643
 644         /* We're done, all's well */
 645         return 1;
 646 }
 647
 648 /**
 649  * alloc_read_gpt_entries(): reads partition entries from disk
 650  * @dev_desc
 651  * @gpt - GPT header
 652  *
 653  * Description: Returns ptes on success,  NULL on error.
 654  * Allocates space for PTEs based on information found in @gpt.
 655  * Notes: remember to free pte when you're done!
 656  */
 657 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
 658                                          gpt_header * pgpt_head)
 659 {
 660         size_t count = 0;
 661         gpt_entry *pte = NULL;
 662
 663         if (!dev_desc || !pgpt_head) {
 664                 printf("%s: Invalid Argument(s)\n", __func__);
 665                 return NULL;
 666         }
 667
 668         count = le32_to_cpu(pgpt_head->num_partition_entries) *
 669                 le32_to_cpu(pgpt_head->sizeof_partition_entry);
 670
 671         debug("%s: count = %u * %u = %zu\n", __func__,
 672               (u32) le32_to_cpu(pgpt_head->num_partition_entries),
 673               (u32) le32_to_cpu(pgpt_head->sizeof_partition_entry), count);
 674
 675         /* Allocate memory for PTE, remember to FREE */
 676         if (count != 0) {
 677                 pte = memalign(ARCH_DMA_MINALIGN, count);
 678         }
 679
 680         if (count == 0 || pte == NULL) {
 681                 printf("%s: ERROR: Can't allocate 0x%zX "
 682                        "bytes for GPT Entries\n",
 683                         __func__, count);
 684                 return NULL;
 685         }
 686
 687         /* Read GPT Entries from device */
 688         if (dev_desc->block_read (dev_desc->dev,
 689                 le64_to_cpu(pgpt_head->partition_entry_lba),
 690                 (lbaint_t) (count / GPT_BLOCK_SIZE), pte)
 691                 != (count / GPT_BLOCK_SIZE)) {
 692
 693                 printf("*** ERROR: Can't read GPT Entries ***\n");
 694                 free(pte);
 695                 return NULL;
 696         }
 697         return pte;
 698 }
 699
 700 /**
 701  * is_pte_valid(): validates a single Partition Table Entry
 702  * @gpt_entry - Pointer to a single Partition Table Entry
 703  *
 704  * Description: returns 1 if valid,  0 on error.
 705  */
 706 static int is_pte_valid(gpt_entry * pte)
 707 {
 708         efi_guid_t unused_guid;
 709
 710         if (!pte) {
 711                 printf("%s: Invalid Argument(s)\n", __func__);
 712                 return 0;
 713         }
 714
 715         /* Only one validation for now:
 716          * The GUID Partition Type != Unused Entry (ALL-ZERO)
 717          */
 718         memset(unused_guid.b, 0, sizeof(unused_guid.b));
 719
 720         if (memcmp(pte->partition_type_guid.b, unused_guid.b,
 721                 sizeof(unused_guid.b)) == 0) {
 722
 723                 debug("%s: Found an unused PTE GUID at 0x%08X\n", __func__,
 724                       (unsigned int)(uintptr_t)pte);
 725
 726                 return 0;
 727         } else {
 728                 return 1;
 729         }
 730 }
 731 #endif