1 /* 2 * Copyright (C) 2008 RuggedCom, Inc. 3 * Richard Retanubun <RichardRetanubun@RuggedCom.com> 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 /* 9 * Problems with CONFIG_SYS_64BIT_LBA: 10 * 11 * struct disk_partition.start in include/part.h is sized as ulong. 12 * When CONFIG_SYS_64BIT_LBA is activated, lbaint_t changes from ulong to uint64_t. 13 * For now, it is cast back to ulong at assignment. 14 * 15 * This limits the maximum size of addressable storage to < 2 Terra Bytes 16 */ 17 #include <asm/unaligned.h> 18 #include <common.h> 19 #include <command.h> 20 #include <ide.h> 21 #include <malloc.h> 22 #include <part_efi.h> 23 #include <linux/ctype.h> 24 25 DECLARE_GLOBAL_DATA_PTR; 26 27 #ifdef HAVE_BLOCK_DEVICE 28 /** 29 * efi_crc32() - EFI version of crc32 function 30 * @buf: buffer to calculate crc32 of 31 * @len - length of buf 32 * 33 * Description: Returns EFI-style CRC32 value for @buf 34 */ 35 static inline u32 efi_crc32(const void *buf, u32 len) 36 { 37 return crc32(0, buf, len); 38 } 39 40 /* 41 * Private function prototypes 42 */ 43 44 static int pmbr_part_valid(struct partition *part); 45 static int is_pmbr_valid(legacy_mbr * mbr); 46 static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba, 47 gpt_header * pgpt_head, gpt_entry ** pgpt_pte); 48 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc, 49 gpt_header * pgpt_head); 50 static int is_pte_valid(gpt_entry * pte); 51 52 static char *print_efiname(gpt_entry *pte) 53 { 54 static char name[PARTNAME_SZ + 1]; 55 int i; 56 for (i = 0; i < PARTNAME_SZ; i++) { 57 u8 c; 58 c = pte->partition_name[i] & 0xff; 59 c = (c && !isprint(c)) ? '.' : c; 60 name[i] = c; 61 } 62 name[PARTNAME_SZ] = 0; 63 return name; 64 } 65 66 static efi_guid_t system_guid = PARTITION_SYSTEM_GUID; 67 68 static inline int is_bootable(gpt_entry *p) 69 { 70 return p->attributes.fields.legacy_bios_bootable || 71 !memcmp(&(p->partition_type_guid), &system_guid, 72 sizeof(efi_guid_t)); 73 } 74 75 #ifdef CONFIG_EFI_PARTITION 76 /* 77 * Public Functions (include/part.h) 78 */ 79 80 void print_part_efi(block_dev_desc_t * dev_desc) 81 { 82 ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz); 83 gpt_entry *gpt_pte = NULL; 84 int i = 0; 85 char uuid[37]; 86 unsigned char *uuid_bin; 87 88 if (!dev_desc) { 89 printf("%s: Invalid Argument(s)\n", __func__); 90 return; 91 } 92 /* This function validates AND fills in the GPT header and PTE */ 93 if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA, 94 gpt_head, &gpt_pte) != 1) { 95 printf("%s: *** ERROR: Invalid GPT ***\n", __func__); 96 return; 97 } 98 99 debug("%s: gpt-entry at %p\n", __func__, gpt_pte); 100 101 printf("Part\tStart LBA\tEnd LBA\t\tName\n"); 102 printf("\tAttributes\n"); 103 printf("\tType UUID\n"); 104 printf("\tPartition UUID\n"); 105 106 for (i = 0; i < le32_to_cpu(gpt_head->num_partition_entries); i++) { 107 /* Stop at the first non valid PTE */ 108 if (!is_pte_valid(&gpt_pte[i])) 109 break; 110 111 printf("%3d\t0x%08llx\t0x%08llx\t\"%s\"\n", (i + 1), 112 le64_to_cpu(gpt_pte[i].starting_lba), 113 le64_to_cpu(gpt_pte[i].ending_lba), 114 print_efiname(&gpt_pte[i])); 115 printf("\tattrs:\t0x%016llx\n", gpt_pte[i].attributes.raw); 116 uuid_bin = (unsigned char *)gpt_pte[i].partition_type_guid.b; 117 uuid_bin_to_str(uuid_bin, uuid); 118 printf("\ttype:\t%s\n", uuid); 119 uuid_bin = (unsigned char *)gpt_pte[i].unique_partition_guid.b; 120 uuid_bin_to_str(uuid_bin, uuid); 121 printf("\tuuid:\t%s\n", uuid); 122 } 123 124 /* Remember to free pte */ 125 free(gpt_pte); 126 return; 127 } 128 129 int get_partition_info_efi(block_dev_desc_t * dev_desc, int part, 130 disk_partition_t * info) 131 { 132 ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz); 133 gpt_entry *gpt_pte = NULL; 134 135 /* "part" argument must be at least 1 */ 136 if (!dev_desc || !info || part < 1) { 137 printf("%s: Invalid Argument(s)\n", __func__); 138 return -1; 139 } 140 141 /* This function validates AND fills in the GPT header and PTE */ 142 if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA, 143 gpt_head, &gpt_pte) != 1) { 144 printf("%s: *** ERROR: Invalid GPT ***\n", __func__); 145 return -1; 146 } 147 148 if (part > le32_to_cpu(gpt_head->num_partition_entries) || 149 !is_pte_valid(&gpt_pte[part - 1])) { 150 debug("%s: *** ERROR: Invalid partition number %d ***\n", 151 __func__, part); 152 free(gpt_pte); 153 return -1; 154 } 155 156 /* The ulong casting limits the maximum disk size to 2 TB */ 157 info->start = (u64)le64_to_cpu(gpt_pte[part - 1].starting_lba); 158 /* The ending LBA is inclusive, to calculate size, add 1 to it */ 159 info->size = ((u64)le64_to_cpu(gpt_pte[part - 1].ending_lba) + 1) 160 - info->start; 161 info->blksz = dev_desc->blksz; 162 163 sprintf((char *)info->name, "%s", 164 print_efiname(&gpt_pte[part - 1])); 165 sprintf((char *)info->type, "U-Boot"); 166 info->bootable = is_bootable(&gpt_pte[part - 1]); 167 #ifdef CONFIG_PARTITION_UUIDS 168 uuid_bin_to_str(gpt_pte[part - 1].unique_partition_guid.b, info->uuid); 169 #endif 170 171 debug("%s: start 0x" LBAF ", size 0x" LBAF ", name %s", __func__, 172 info->start, info->size, info->name); 173 174 /* Remember to free pte */ 175 free(gpt_pte); 176 return 0; 177 } 178 179 int test_part_efi(block_dev_desc_t * dev_desc) 180 { 181 ALLOC_CACHE_ALIGN_BUFFER_PAD(legacy_mbr, legacymbr, 1, dev_desc->blksz); 182 183 /* Read legacy MBR from block 0 and validate it */ 184 if ((dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *)legacymbr) != 1) 185 || (is_pmbr_valid(legacymbr) != 1)) { 186 return -1; 187 } 188 return 0; 189 } 190 191 /** 192 * set_protective_mbr(): Set the EFI protective MBR 193 * @param dev_desc - block device descriptor 194 * 195 * @return - zero on success, otherwise error 196 */ 197 static int set_protective_mbr(block_dev_desc_t *dev_desc) 198 { 199 /* Setup the Protective MBR */ 200 ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, p_mbr, 1); 201 memset(p_mbr, 0, sizeof(*p_mbr)); 202 203 if (p_mbr == NULL) { 204 printf("%s: calloc failed!\n", __func__); 205 return -1; 206 } 207 /* Append signature */ 208 p_mbr->signature = MSDOS_MBR_SIGNATURE; 209 p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT; 210 p_mbr->partition_record[0].start_sect = 1; 211 p_mbr->partition_record[0].nr_sects = (u32) dev_desc->lba; 212 213 /* Write MBR sector to the MMC device */ 214 if (dev_desc->block_write(dev_desc->dev, 0, 1, p_mbr) != 1) { 215 printf("** Can't write to device %d **\n", 216 dev_desc->dev); 217 return -1; 218 } 219 220 return 0; 221 } 222 223 int write_gpt_table(block_dev_desc_t *dev_desc, 224 gpt_header *gpt_h, gpt_entry *gpt_e) 225 { 226 const int pte_blk_cnt = BLOCK_CNT((gpt_h->num_partition_entries 227 * sizeof(gpt_entry)), dev_desc); 228 u32 calc_crc32; 229 u64 val; 230 231 debug("max lba: %x\n", (u32) dev_desc->lba); 232 /* Setup the Protective MBR */ 233 if (set_protective_mbr(dev_desc) < 0) 234 goto err; 235 236 /* Generate CRC for the Primary GPT Header */ 237 calc_crc32 = efi_crc32((const unsigned char *)gpt_e, 238 le32_to_cpu(gpt_h->num_partition_entries) * 239 le32_to_cpu(gpt_h->sizeof_partition_entry)); 240 gpt_h->partition_entry_array_crc32 = cpu_to_le32(calc_crc32); 241 242 calc_crc32 = efi_crc32((const unsigned char *)gpt_h, 243 le32_to_cpu(gpt_h->header_size)); 244 gpt_h->header_crc32 = cpu_to_le32(calc_crc32); 245 246 /* Write the First GPT to the block right after the Legacy MBR */ 247 if (dev_desc->block_write(dev_desc->dev, 1, 1, gpt_h) != 1) 248 goto err; 249 250 if (dev_desc->block_write(dev_desc->dev, 2, pte_blk_cnt, gpt_e) 251 != pte_blk_cnt) 252 goto err; 253 254 /* recalculate the values for the Second GPT Header */ 255 val = le64_to_cpu(gpt_h->my_lba); 256 gpt_h->my_lba = gpt_h->alternate_lba; 257 gpt_h->alternate_lba = cpu_to_le64(val); 258 gpt_h->header_crc32 = 0; 259 260 calc_crc32 = efi_crc32((const unsigned char *)gpt_h, 261 le32_to_cpu(gpt_h->header_size)); 262 gpt_h->header_crc32 = cpu_to_le32(calc_crc32); 263 264 if (dev_desc->block_write(dev_desc->dev, 265 le32_to_cpu(gpt_h->last_usable_lba + 1), 266 pte_blk_cnt, gpt_e) != pte_blk_cnt) 267 goto err; 268 269 if (dev_desc->block_write(dev_desc->dev, 270 le32_to_cpu(gpt_h->my_lba), 1, gpt_h) != 1) 271 goto err; 272 273 debug("GPT successfully written to block device!\n"); 274 return 0; 275 276 err: 277 printf("** Can't write to device %d **\n", dev_desc->dev); 278 return -1; 279 } 280 281 int gpt_fill_pte(gpt_header *gpt_h, gpt_entry *gpt_e, 282 disk_partition_t *partitions, int parts) 283 { 284 u32 offset = (u32)le32_to_cpu(gpt_h->first_usable_lba); 285 ulong start; 286 int i, k; 287 size_t efiname_len, dosname_len; 288 #ifdef CONFIG_PARTITION_UUIDS 289 char *str_uuid; 290 unsigned char *bin_uuid; 291 #endif 292 293 for (i = 0; i < parts; i++) { 294 /* partition starting lba */ 295 start = partitions[i].start; 296 if (start && (start < offset)) { 297 printf("Partition overlap\n"); 298 return -1; 299 } 300 if (start) { 301 gpt_e[i].starting_lba = cpu_to_le64(start); 302 offset = start + partitions[i].size; 303 } else { 304 gpt_e[i].starting_lba = cpu_to_le64(offset); 305 offset += partitions[i].size; 306 } 307 if (offset >= gpt_h->last_usable_lba) { 308 printf("Partitions layout exceds disk size\n"); 309 return -1; 310 } 311 /* partition ending lba */ 312 if ((i == parts - 1) && (partitions[i].size == 0)) 313 /* extend the last partition to maximuim */ 314 gpt_e[i].ending_lba = gpt_h->last_usable_lba; 315 else 316 gpt_e[i].ending_lba = cpu_to_le64(offset - 1); 317 318 /* partition type GUID */ 319 memcpy(gpt_e[i].partition_type_guid.b, 320 &PARTITION_BASIC_DATA_GUID, 16); 321 322 #ifdef CONFIG_PARTITION_UUIDS 323 str_uuid = partitions[i].uuid; 324 bin_uuid = gpt_e[i].unique_partition_guid.b; 325 326 if (uuid_str_to_bin(str_uuid, bin_uuid)) { 327 printf("Partition no. %d: invalid guid: %s\n", 328 i, str_uuid); 329 return -1; 330 } 331 #endif 332 333 /* partition attributes */ 334 memset(&gpt_e[i].attributes, 0, 335 sizeof(gpt_entry_attributes)); 336 337 /* partition name */ 338 efiname_len = sizeof(gpt_e[i].partition_name) 339 / sizeof(efi_char16_t); 340 dosname_len = sizeof(partitions[i].name); 341 342 memset(gpt_e[i].partition_name, 0, 343 sizeof(gpt_e[i].partition_name)); 344 345 for (k = 0; k < min(dosname_len, efiname_len); k++) 346 gpt_e[i].partition_name[k] = 347 (efi_char16_t)(partitions[i].name[k]); 348 349 debug("%s: name: %s offset[%d]: 0x%x size[%d]: 0x" LBAF "\n", 350 __func__, partitions[i].name, i, 351 offset, i, partitions[i].size); 352 } 353 354 return 0; 355 } 356 357 int gpt_fill_header(block_dev_desc_t *dev_desc, gpt_header *gpt_h, 358 char *str_guid, int parts_count) 359 { 360 gpt_h->signature = cpu_to_le64(GPT_HEADER_SIGNATURE); 361 gpt_h->revision = cpu_to_le32(GPT_HEADER_REVISION_V1); 362 gpt_h->header_size = cpu_to_le32(sizeof(gpt_header)); 363 gpt_h->my_lba = cpu_to_le64(1); 364 gpt_h->alternate_lba = cpu_to_le64(dev_desc->lba - 1); 365 gpt_h->first_usable_lba = cpu_to_le64(34); 366 gpt_h->last_usable_lba = cpu_to_le64(dev_desc->lba - 34); 367 gpt_h->partition_entry_lba = cpu_to_le64(2); 368 gpt_h->num_partition_entries = cpu_to_le32(GPT_ENTRY_NUMBERS); 369 gpt_h->sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry)); 370 gpt_h->header_crc32 = 0; 371 gpt_h->partition_entry_array_crc32 = 0; 372 373 if (uuid_str_to_bin(str_guid, gpt_h->disk_guid.b)) 374 return -1; 375 376 return 0; 377 } 378 379 int gpt_restore(block_dev_desc_t *dev_desc, char *str_disk_guid, 380 disk_partition_t *partitions, int parts_count) 381 { 382 int ret; 383 384 gpt_header *gpt_h = calloc(1, PAD_TO_BLOCKSIZE(sizeof(gpt_header), 385 dev_desc)); 386 gpt_entry *gpt_e; 387 388 if (gpt_h == NULL) { 389 printf("%s: calloc failed!\n", __func__); 390 return -1; 391 } 392 393 gpt_e = calloc(1, PAD_TO_BLOCKSIZE(GPT_ENTRY_NUMBERS 394 * sizeof(gpt_entry), 395 dev_desc)); 396 if (gpt_e == NULL) { 397 printf("%s: calloc failed!\n", __func__); 398 free(gpt_h); 399 return -1; 400 } 401 402 /* Generate Primary GPT header (LBA1) */ 403 ret = gpt_fill_header(dev_desc, gpt_h, str_disk_guid, parts_count); 404 if (ret) 405 goto err; 406 407 /* Generate partition entries */ 408 ret = gpt_fill_pte(gpt_h, gpt_e, partitions, parts_count); 409 if (ret) 410 goto err; 411 412 /* Write GPT partition table */ 413 ret = write_gpt_table(dev_desc, gpt_h, gpt_e); 414 415 err: 416 free(gpt_e); 417 free(gpt_h); 418 return ret; 419 } 420 #endif 421 422 /* 423 * Private functions 424 */ 425 /* 426 * pmbr_part_valid(): Check for EFI partition signature 427 * 428 * Returns: 1 if EFI GPT partition type is found. 429 */ 430 static int pmbr_part_valid(struct partition *part) 431 { 432 if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT && 433 get_unaligned_le32(&part->start_sect) == 1UL) { 434 return 1; 435 } 436 437 return 0; 438 } 439 440 /* 441 * is_pmbr_valid(): test Protective MBR for validity 442 * 443 * Returns: 1 if PMBR is valid, 0 otherwise. 444 * Validity depends on two things: 445 * 1) MSDOS signature is in the last two bytes of the MBR 446 * 2) One partition of type 0xEE is found, checked by pmbr_part_valid() 447 */ 448 static int is_pmbr_valid(legacy_mbr * mbr) 449 { 450 int i = 0; 451 452 if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE) 453 return 0; 454 455 for (i = 0; i < 4; i++) { 456 if (pmbr_part_valid(&mbr->partition_record[i])) { 457 return 1; 458 } 459 } 460 return 0; 461 } 462 463 /** 464 * is_gpt_valid() - tests one GPT header and PTEs for validity 465 * 466 * lba is the logical block address of the GPT header to test 467 * gpt is a GPT header ptr, filled on return. 468 * ptes is a PTEs ptr, filled on return. 469 * 470 * Description: returns 1 if valid, 0 on error. 471 * If valid, returns pointers to PTEs. 472 */ 473 static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba, 474 gpt_header * pgpt_head, gpt_entry ** pgpt_pte) 475 { 476 u32 crc32_backup = 0; 477 u32 calc_crc32; 478 unsigned long long lastlba; 479 480 if (!dev_desc || !pgpt_head) { 481 printf("%s: Invalid Argument(s)\n", __func__); 482 return 0; 483 } 484 485 /* Read GPT Header from device */ 486 if (dev_desc->block_read(dev_desc->dev, lba, 1, pgpt_head) != 1) { 487 printf("*** ERROR: Can't read GPT header ***\n"); 488 return 0; 489 } 490 491 /* Check the GPT header signature */ 492 if (le64_to_cpu(pgpt_head->signature) != GPT_HEADER_SIGNATURE) { 493 printf("GUID Partition Table Header signature is wrong:" 494 "0x%llX != 0x%llX\n", 495 le64_to_cpu(pgpt_head->signature), 496 GPT_HEADER_SIGNATURE); 497 return 0; 498 } 499 500 /* Check the GUID Partition Table CRC */ 501 memcpy(&crc32_backup, &pgpt_head->header_crc32, sizeof(crc32_backup)); 502 memset(&pgpt_head->header_crc32, 0, sizeof(pgpt_head->header_crc32)); 503 504 calc_crc32 = efi_crc32((const unsigned char *)pgpt_head, 505 le32_to_cpu(pgpt_head->header_size)); 506 507 memcpy(&pgpt_head->header_crc32, &crc32_backup, sizeof(crc32_backup)); 508 509 if (calc_crc32 != le32_to_cpu(crc32_backup)) { 510 printf("GUID Partition Table Header CRC is wrong:" 511 "0x%x != 0x%x\n", 512 le32_to_cpu(crc32_backup), calc_crc32); 513 return 0; 514 } 515 516 /* Check that the my_lba entry points to the LBA that contains the GPT */ 517 if (le64_to_cpu(pgpt_head->my_lba) != lba) { 518 printf("GPT: my_lba incorrect: %llX != %llX\n", 519 le64_to_cpu(pgpt_head->my_lba), 520 lba); 521 return 0; 522 } 523 524 /* Check the first_usable_lba and last_usable_lba are within the disk. */ 525 lastlba = (unsigned long long)dev_desc->lba; 526 if (le64_to_cpu(pgpt_head->first_usable_lba) > lastlba) { 527 printf("GPT: first_usable_lba incorrect: %llX > %llX\n", 528 le64_to_cpu(pgpt_head->first_usable_lba), lastlba); 529 return 0; 530 } 531 if (le64_to_cpu(pgpt_head->last_usable_lba) > lastlba) { 532 printf("GPT: last_usable_lba incorrect: %llX > %llX\n", 533 (u64) le64_to_cpu(pgpt_head->last_usable_lba), lastlba); 534 return 0; 535 } 536 537 debug("GPT: first_usable_lba: %llX last_usable_lba %llX last lba %llX\n", 538 le64_to_cpu(pgpt_head->first_usable_lba), 539 le64_to_cpu(pgpt_head->last_usable_lba), lastlba); 540 541 /* Read and allocate Partition Table Entries */ 542 *pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head); 543 if (*pgpt_pte == NULL) { 544 printf("GPT: Failed to allocate memory for PTE\n"); 545 return 0; 546 } 547 548 /* Check the GUID Partition Table Entry Array CRC */ 549 calc_crc32 = efi_crc32((const unsigned char *)*pgpt_pte, 550 le32_to_cpu(pgpt_head->num_partition_entries) * 551 le32_to_cpu(pgpt_head->sizeof_partition_entry)); 552 553 if (calc_crc32 != le32_to_cpu(pgpt_head->partition_entry_array_crc32)) { 554 printf("GUID Partition Table Entry Array CRC is wrong:" 555 "0x%x != 0x%x\n", 556 le32_to_cpu(pgpt_head->partition_entry_array_crc32), 557 calc_crc32); 558 559 free(*pgpt_pte); 560 return 0; 561 } 562 563 /* We're done, all's well */ 564 return 1; 565 } 566 567 /** 568 * alloc_read_gpt_entries(): reads partition entries from disk 569 * @dev_desc 570 * @gpt - GPT header 571 * 572 * Description: Returns ptes on success, NULL on error. 573 * Allocates space for PTEs based on information found in @gpt. 574 * Notes: remember to free pte when you're done! 575 */ 576 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc, 577 gpt_header * pgpt_head) 578 { 579 size_t count = 0, blk_cnt; 580 gpt_entry *pte = NULL; 581 582 if (!dev_desc || !pgpt_head) { 583 printf("%s: Invalid Argument(s)\n", __func__); 584 return NULL; 585 } 586 587 count = le32_to_cpu(pgpt_head->num_partition_entries) * 588 le32_to_cpu(pgpt_head->sizeof_partition_entry); 589 590 debug("%s: count = %u * %u = %zu\n", __func__, 591 (u32) le32_to_cpu(pgpt_head->num_partition_entries), 592 (u32) le32_to_cpu(pgpt_head->sizeof_partition_entry), count); 593 594 /* Allocate memory for PTE, remember to FREE */ 595 if (count != 0) { 596 pte = memalign(ARCH_DMA_MINALIGN, 597 PAD_TO_BLOCKSIZE(count, dev_desc)); 598 } 599 600 if (count == 0 || pte == NULL) { 601 printf("%s: ERROR: Can't allocate 0x%zX " 602 "bytes for GPT Entries\n", 603 __func__, count); 604 return NULL; 605 } 606 607 /* Read GPT Entries from device */ 608 blk_cnt = BLOCK_CNT(count, dev_desc); 609 if (dev_desc->block_read (dev_desc->dev, 610 le64_to_cpu(pgpt_head->partition_entry_lba), 611 (lbaint_t) (blk_cnt), pte) 612 != blk_cnt) { 613 614 printf("*** ERROR: Can't read GPT Entries ***\n"); 615 free(pte); 616 return NULL; 617 } 618 return pte; 619 } 620 621 /** 622 * is_pte_valid(): validates a single Partition Table Entry 623 * @gpt_entry - Pointer to a single Partition Table Entry 624 * 625 * Description: returns 1 if valid, 0 on error. 626 */ 627 static int is_pte_valid(gpt_entry * pte) 628 { 629 efi_guid_t unused_guid; 630 631 if (!pte) { 632 printf("%s: Invalid Argument(s)\n", __func__); 633 return 0; 634 } 635 636 /* Only one validation for now: 637 * The GUID Partition Type != Unused Entry (ALL-ZERO) 638 */ 639 memset(unused_guid.b, 0, sizeof(unused_guid.b)); 640 641 if (memcmp(pte->partition_type_guid.b, unused_guid.b, 642 sizeof(unused_guid.b)) == 0) { 643 644 debug("%s: Found an unused PTE GUID at 0x%08X\n", __func__, 645 (unsigned int)(uintptr_t)pte); 646 647 return 0; 648 } else { 649 return 1; 650 } 651 } 652 #endif 653