1 /************************************************************ 2 * EFI GUID Partition Table handling 3 * 4 * http://www.uefi.org/specs/ 5 * http://www.intel.com/technology/efi/ 6 * 7 * efi.[ch] by Matt Domsch <Matt_Domsch@dell.com> 8 * Copyright 2000,2001,2002,2004 Dell Inc. 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or 13 * (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 23 * 24 * 25 * TODO: 26 * 27 * Changelog: 28 * Mon August 5th, 2013 Davidlohr Bueso <davidlohr@hp.com> 29 * - detect hybrid MBRs, tighter pMBR checking & cleanups. 30 * 31 * Mon Nov 09 2004 Matt Domsch <Matt_Domsch@dell.com> 32 * - test for valid PMBR and valid PGPT before ever reading 33 * AGPT, allow override with 'gpt' kernel command line option. 34 * - check for first/last_usable_lba outside of size of disk 35 * 36 * Tue Mar 26 2002 Matt Domsch <Matt_Domsch@dell.com> 37 * - Ported to 2.5.7-pre1 and 2.5.7-dj2 38 * - Applied patch to avoid fault in alternate header handling 39 * - cleaned up find_valid_gpt 40 * - On-disk structure and copy in memory is *always* LE now - 41 * swab fields as needed 42 * - remove print_gpt_header() 43 * - only use first max_p partition entries, to keep the kernel minor number 44 * and partition numbers tied. 45 * 46 * Mon Feb 04 2002 Matt Domsch <Matt_Domsch@dell.com> 47 * - Removed __PRIPTR_PREFIX - not being used 48 * 49 * Mon Jan 14 2002 Matt Domsch <Matt_Domsch@dell.com> 50 * - Ported to 2.5.2-pre11 + library crc32 patch Linus applied 51 * 52 * Thu Dec 6 2001 Matt Domsch <Matt_Domsch@dell.com> 53 * - Added compare_gpts(). 54 * - moved le_efi_guid_to_cpus() back into this file. GPT is the only 55 * thing that keeps EFI GUIDs on disk. 56 * - Changed gpt structure names and members to be simpler and more Linux-like. 57 * 58 * Wed Oct 17 2001 Matt Domsch <Matt_Domsch@dell.com> 59 * - Removed CONFIG_DEVFS_VOLUMES_UUID code entirely per Martin Wilck 60 * 61 * Wed Oct 10 2001 Matt Domsch <Matt_Domsch@dell.com> 62 * - Changed function comments to DocBook style per Andreas Dilger suggestion. 63 * 64 * Mon Oct 08 2001 Matt Domsch <Matt_Domsch@dell.com> 65 * - Change read_lba() to use the page cache per Al Viro's work. 66 * - print u64s properly on all architectures 67 * - fixed debug_printk(), now Dprintk() 68 * 69 * Mon Oct 01 2001 Matt Domsch <Matt_Domsch@dell.com> 70 * - Style cleanups 71 * - made most functions static 72 * - Endianness addition 73 * - remove test for second alternate header, as it's not per spec, 74 * and is unnecessary. There's now a method to read/write the last 75 * sector of an odd-sized disk from user space. No tools have ever 76 * been released which used this code, so it's effectively dead. 77 * - Per Asit Mallick of Intel, added a test for a valid PMBR. 78 * - Added kernel command line option 'gpt' to override valid PMBR test. 79 * 80 * Wed Jun 6 2001 Martin Wilck <Martin.Wilck@Fujitsu-Siemens.com> 81 * - added devfs volume UUID support (/dev/volumes/uuids) for 82 * mounting file systems by the partition GUID. 83 * 84 * Tue Dec 5 2000 Matt Domsch <Matt_Domsch@dell.com> 85 * - Moved crc32() to linux/lib, added efi_crc32(). 86 * 87 * Thu Nov 30 2000 Matt Domsch <Matt_Domsch@dell.com> 88 * - Replaced Intel's CRC32 function with an equivalent 89 * non-license-restricted version. 90 * 91 * Wed Oct 25 2000 Matt Domsch <Matt_Domsch@dell.com> 92 * - Fixed the last_lba() call to return the proper last block 93 * 94 * Thu Oct 12 2000 Matt Domsch <Matt_Domsch@dell.com> 95 * - Thanks to Andries Brouwer for his debugging assistance. 96 * - Code works, detects all the partitions. 97 * 98 ************************************************************/ 99 #include <linux/crc32.h> 100 #include <linux/ctype.h> 101 #include <linux/math64.h> 102 #include <linux/slab.h> 103 #include "check.h" 104 #include "efi.h" 105 106 /* This allows a kernel command line option 'gpt' to override 107 * the test for invalid PMBR. Not __initdata because reloading 108 * the partition tables happens after init too. 109 */ 110 static int force_gpt; 111 static int __init 112 force_gpt_fn(char *str) 113 { 114 force_gpt = 1; 115 return 1; 116 } 117 __setup("gpt", force_gpt_fn); 118 119 120 /** 121 * efi_crc32() - EFI version of crc32 function 122 * @buf: buffer to calculate crc32 of 123 * @len - length of buf 124 * 125 * Description: Returns EFI-style CRC32 value for @buf 126 * 127 * This function uses the little endian Ethernet polynomial 128 * but seeds the function with ~0, and xor's with ~0 at the end. 129 * Note, the EFI Specification, v1.02, has a reference to 130 * Dr. Dobbs Journal, May 1994 (actually it's in May 1992). 131 */ 132 static inline u32 133 efi_crc32(const void *buf, unsigned long len) 134 { 135 return (crc32(~0L, buf, len) ^ ~0L); 136 } 137 138 /** 139 * last_lba(): return number of last logical block of device 140 * @bdev: block device 141 * 142 * Description: Returns last LBA value on success, 0 on error. 143 * This is stored (by sd and ide-geometry) in 144 * the part[0] entry for this disk, and is the number of 145 * physical sectors available on the disk. 146 */ 147 static u64 last_lba(struct block_device *bdev) 148 { 149 if (!bdev || !bdev->bd_inode) 150 return 0; 151 return div_u64(bdev->bd_inode->i_size, 152 bdev_logical_block_size(bdev)) - 1ULL; 153 } 154 155 static inline int pmbr_part_valid(gpt_mbr_record *part) 156 { 157 if (part->os_type != EFI_PMBR_OSTYPE_EFI_GPT) 158 goto invalid; 159 160 /* set to 0x00000001 (i.e., the LBA of the GPT Partition Header) */ 161 if (le32_to_cpu(part->starting_lba) != GPT_PRIMARY_PARTITION_TABLE_LBA) 162 goto invalid; 163 164 return GPT_MBR_PROTECTIVE; 165 invalid: 166 return 0; 167 } 168 169 /** 170 * is_pmbr_valid(): test Protective MBR for validity 171 * @mbr: pointer to a legacy mbr structure 172 * @total_sectors: amount of sectors in the device 173 * 174 * Description: Checks for a valid protective or hybrid 175 * master boot record (MBR). The validity of a pMBR depends 176 * on all of the following properties: 177 * 1) MSDOS signature is in the last two bytes of the MBR 178 * 2) One partition of type 0xEE is found 179 * 180 * In addition, a hybrid MBR will have up to three additional 181 * primary partitions, which point to the same space that's 182 * marked out by up to three GPT partitions. 183 * 184 * Returns 0 upon invalid MBR, or GPT_MBR_PROTECTIVE or 185 * GPT_MBR_HYBRID depending on the device layout. 186 */ 187 static int is_pmbr_valid(legacy_mbr *mbr, sector_t total_sectors) 188 { 189 int i, part = 0, ret = 0; /* invalid by default */ 190 191 if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE) 192 goto done; 193 194 for (i = 0; i < 4; i++) { 195 ret = pmbr_part_valid(&mbr->partition_record[i]); 196 if (ret == GPT_MBR_PROTECTIVE) { 197 part = i; 198 /* 199 * Ok, we at least know that there's a protective MBR, 200 * now check if there are other partition types for 201 * hybrid MBR. 202 */ 203 goto check_hybrid; 204 } 205 } 206 207 if (ret != GPT_MBR_PROTECTIVE) 208 goto done; 209 check_hybrid: 210 for (i = 0; i < 4; i++) 211 if ((mbr->partition_record[i].os_type != 212 EFI_PMBR_OSTYPE_EFI_GPT) && 213 (mbr->partition_record[i].os_type != 0x00)) 214 ret = GPT_MBR_HYBRID; 215 216 /* 217 * Protective MBRs take up the lesser of the whole disk 218 * or 2 TiB (32bit LBA), ignoring the rest of the disk. 219 * 220 * Hybrid MBRs do not necessarily comply with this. 221 */ 222 if (ret == GPT_MBR_PROTECTIVE) { 223 if (le32_to_cpu(mbr->partition_record[part].size_in_lba) != 224 min((uint32_t) total_sectors - 1, 0xFFFFFFFF)) 225 ret = 0; 226 } 227 done: 228 return ret; 229 } 230 231 /** 232 * read_lba(): Read bytes from disk, starting at given LBA 233 * @state 234 * @lba 235 * @buffer 236 * @size_t 237 * 238 * Description: Reads @count bytes from @state->bdev into @buffer. 239 * Returns number of bytes read on success, 0 on error. 240 */ 241 static size_t read_lba(struct parsed_partitions *state, 242 u64 lba, u8 *buffer, size_t count) 243 { 244 size_t totalreadcount = 0; 245 struct block_device *bdev = state->bdev; 246 sector_t n = lba * (bdev_logical_block_size(bdev) / 512); 247 248 if (!buffer || lba > last_lba(bdev)) 249 return 0; 250 251 while (count) { 252 int copied = 512; 253 Sector sect; 254 unsigned char *data = read_part_sector(state, n++, §); 255 if (!data) 256 break; 257 if (copied > count) 258 copied = count; 259 memcpy(buffer, data, copied); 260 put_dev_sector(sect); 261 buffer += copied; 262 totalreadcount +=copied; 263 count -= copied; 264 } 265 return totalreadcount; 266 } 267 268 /** 269 * alloc_read_gpt_entries(): reads partition entries from disk 270 * @state 271 * @gpt - GPT header 272 * 273 * Description: Returns ptes on success, NULL on error. 274 * Allocates space for PTEs based on information found in @gpt. 275 * Notes: remember to free pte when you're done! 276 */ 277 static gpt_entry *alloc_read_gpt_entries(struct parsed_partitions *state, 278 gpt_header *gpt) 279 { 280 size_t count; 281 gpt_entry *pte; 282 283 if (!gpt) 284 return NULL; 285 286 count = le32_to_cpu(gpt->num_partition_entries) * 287 le32_to_cpu(gpt->sizeof_partition_entry); 288 if (!count) 289 return NULL; 290 pte = kmalloc(count, GFP_KERNEL); 291 if (!pte) 292 return NULL; 293 294 if (read_lba(state, le64_to_cpu(gpt->partition_entry_lba), 295 (u8 *) pte, count) < count) { 296 kfree(pte); 297 pte=NULL; 298 return NULL; 299 } 300 return pte; 301 } 302 303 /** 304 * alloc_read_gpt_header(): Allocates GPT header, reads into it from disk 305 * @state 306 * @lba is the Logical Block Address of the partition table 307 * 308 * Description: returns GPT header on success, NULL on error. Allocates 309 * and fills a GPT header starting at @ from @state->bdev. 310 * Note: remember to free gpt when finished with it. 311 */ 312 static gpt_header *alloc_read_gpt_header(struct parsed_partitions *state, 313 u64 lba) 314 { 315 gpt_header *gpt; 316 unsigned ssz = bdev_logical_block_size(state->bdev); 317 318 gpt = kmalloc(ssz, GFP_KERNEL); 319 if (!gpt) 320 return NULL; 321 322 if (read_lba(state, lba, (u8 *) gpt, ssz) < ssz) { 323 kfree(gpt); 324 gpt=NULL; 325 return NULL; 326 } 327 328 return gpt; 329 } 330 331 /** 332 * is_gpt_valid() - tests one GPT header and PTEs for validity 333 * @state 334 * @lba is the logical block address of the GPT header to test 335 * @gpt is a GPT header ptr, filled on return. 336 * @ptes is a PTEs ptr, filled on return. 337 * 338 * Description: returns 1 if valid, 0 on error. 339 * If valid, returns pointers to newly allocated GPT header and PTEs. 340 */ 341 static int is_gpt_valid(struct parsed_partitions *state, u64 lba, 342 gpt_header **gpt, gpt_entry **ptes) 343 { 344 u32 crc, origcrc; 345 u64 lastlba; 346 347 if (!ptes) 348 return 0; 349 if (!(*gpt = alloc_read_gpt_header(state, lba))) 350 return 0; 351 352 /* Check the GUID Partition Table signature */ 353 if (le64_to_cpu((*gpt)->signature) != GPT_HEADER_SIGNATURE) { 354 pr_debug("GUID Partition Table Header signature is wrong:" 355 "%lld != %lld\n", 356 (unsigned long long)le64_to_cpu((*gpt)->signature), 357 (unsigned long long)GPT_HEADER_SIGNATURE); 358 goto fail; 359 } 360 361 /* Check the GUID Partition Table header size is too big */ 362 if (le32_to_cpu((*gpt)->header_size) > 363 bdev_logical_block_size(state->bdev)) { 364 pr_debug("GUID Partition Table Header size is too large: %u > %u\n", 365 le32_to_cpu((*gpt)->header_size), 366 bdev_logical_block_size(state->bdev)); 367 goto fail; 368 } 369 370 /* Check the GUID Partition Table header size is too small */ 371 if (le32_to_cpu((*gpt)->header_size) < sizeof(gpt_header)) { 372 pr_debug("GUID Partition Table Header size is too small: %u < %zu\n", 373 le32_to_cpu((*gpt)->header_size), 374 sizeof(gpt_header)); 375 goto fail; 376 } 377 378 /* Check the GUID Partition Table CRC */ 379 origcrc = le32_to_cpu((*gpt)->header_crc32); 380 (*gpt)->header_crc32 = 0; 381 crc = efi_crc32((const unsigned char *) (*gpt), le32_to_cpu((*gpt)->header_size)); 382 383 if (crc != origcrc) { 384 pr_debug("GUID Partition Table Header CRC is wrong: %x != %x\n", 385 crc, origcrc); 386 goto fail; 387 } 388 (*gpt)->header_crc32 = cpu_to_le32(origcrc); 389 390 /* Check that the my_lba entry points to the LBA that contains 391 * the GUID Partition Table */ 392 if (le64_to_cpu((*gpt)->my_lba) != lba) { 393 pr_debug("GPT my_lba incorrect: %lld != %lld\n", 394 (unsigned long long)le64_to_cpu((*gpt)->my_lba), 395 (unsigned long long)lba); 396 goto fail; 397 } 398 399 /* Check the first_usable_lba and last_usable_lba are 400 * within the disk. 401 */ 402 lastlba = last_lba(state->bdev); 403 if (le64_to_cpu((*gpt)->first_usable_lba) > lastlba) { 404 pr_debug("GPT: first_usable_lba incorrect: %lld > %lld\n", 405 (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba), 406 (unsigned long long)lastlba); 407 goto fail; 408 } 409 if (le64_to_cpu((*gpt)->last_usable_lba) > lastlba) { 410 pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n", 411 (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba), 412 (unsigned long long)lastlba); 413 goto fail; 414 } 415 if (le64_to_cpu((*gpt)->last_usable_lba) < le64_to_cpu((*gpt)->first_usable_lba)) { 416 pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n", 417 (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba), 418 (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba)); 419 goto fail; 420 } 421 /* Check that sizeof_partition_entry has the correct value */ 422 if (le32_to_cpu((*gpt)->sizeof_partition_entry) != sizeof(gpt_entry)) { 423 pr_debug("GUID Partitition Entry Size check failed.\n"); 424 goto fail; 425 } 426 427 if (!(*ptes = alloc_read_gpt_entries(state, *gpt))) 428 goto fail; 429 430 /* Check the GUID Partition Entry Array CRC */ 431 crc = efi_crc32((const unsigned char *) (*ptes), 432 le32_to_cpu((*gpt)->num_partition_entries) * 433 le32_to_cpu((*gpt)->sizeof_partition_entry)); 434 435 if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) { 436 pr_debug("GUID Partitition Entry Array CRC check failed.\n"); 437 goto fail_ptes; 438 } 439 440 /* We're done, all's well */ 441 return 1; 442 443 fail_ptes: 444 kfree(*ptes); 445 *ptes = NULL; 446 fail: 447 kfree(*gpt); 448 *gpt = NULL; 449 return 0; 450 } 451 452 /** 453 * is_pte_valid() - tests one PTE for validity 454 * @pte is the pte to check 455 * @lastlba is last lba of the disk 456 * 457 * Description: returns 1 if valid, 0 on error. 458 */ 459 static inline int 460 is_pte_valid(const gpt_entry *pte, const u64 lastlba) 461 { 462 if ((!efi_guidcmp(pte->partition_type_guid, NULL_GUID)) || 463 le64_to_cpu(pte->starting_lba) > lastlba || 464 le64_to_cpu(pte->ending_lba) > lastlba) 465 return 0; 466 return 1; 467 } 468 469 /** 470 * compare_gpts() - Search disk for valid GPT headers and PTEs 471 * @pgpt is the primary GPT header 472 * @agpt is the alternate GPT header 473 * @lastlba is the last LBA number 474 * Description: Returns nothing. Sanity checks pgpt and agpt fields 475 * and prints warnings on discrepancies. 476 * 477 */ 478 static void 479 compare_gpts(gpt_header *pgpt, gpt_header *agpt, u64 lastlba) 480 { 481 int error_found = 0; 482 if (!pgpt || !agpt) 483 return; 484 if (le64_to_cpu(pgpt->my_lba) != le64_to_cpu(agpt->alternate_lba)) { 485 pr_warn("GPT:Primary header LBA != Alt. header alternate_lba\n"); 486 pr_warn("GPT:%lld != %lld\n", 487 (unsigned long long)le64_to_cpu(pgpt->my_lba), 488 (unsigned long long)le64_to_cpu(agpt->alternate_lba)); 489 error_found++; 490 } 491 if (le64_to_cpu(pgpt->alternate_lba) != le64_to_cpu(agpt->my_lba)) { 492 pr_warn("GPT:Primary header alternate_lba != Alt. header my_lba\n"); 493 pr_warn("GPT:%lld != %lld\n", 494 (unsigned long long)le64_to_cpu(pgpt->alternate_lba), 495 (unsigned long long)le64_to_cpu(agpt->my_lba)); 496 error_found++; 497 } 498 if (le64_to_cpu(pgpt->first_usable_lba) != 499 le64_to_cpu(agpt->first_usable_lba)) { 500 pr_warn("GPT:first_usable_lbas don't match.\n"); 501 pr_warn("GPT:%lld != %lld\n", 502 (unsigned long long)le64_to_cpu(pgpt->first_usable_lba), 503 (unsigned long long)le64_to_cpu(agpt->first_usable_lba)); 504 error_found++; 505 } 506 if (le64_to_cpu(pgpt->last_usable_lba) != 507 le64_to_cpu(agpt->last_usable_lba)) { 508 pr_warn("GPT:last_usable_lbas don't match.\n"); 509 pr_warn("GPT:%lld != %lld\n", 510 (unsigned long long)le64_to_cpu(pgpt->last_usable_lba), 511 (unsigned long long)le64_to_cpu(agpt->last_usable_lba)); 512 error_found++; 513 } 514 if (efi_guidcmp(pgpt->disk_guid, agpt->disk_guid)) { 515 pr_warn("GPT:disk_guids don't match.\n"); 516 error_found++; 517 } 518 if (le32_to_cpu(pgpt->num_partition_entries) != 519 le32_to_cpu(agpt->num_partition_entries)) { 520 pr_warn("GPT:num_partition_entries don't match: " 521 "0x%x != 0x%x\n", 522 le32_to_cpu(pgpt->num_partition_entries), 523 le32_to_cpu(agpt->num_partition_entries)); 524 error_found++; 525 } 526 if (le32_to_cpu(pgpt->sizeof_partition_entry) != 527 le32_to_cpu(agpt->sizeof_partition_entry)) { 528 pr_warn("GPT:sizeof_partition_entry values don't match: " 529 "0x%x != 0x%x\n", 530 le32_to_cpu(pgpt->sizeof_partition_entry), 531 le32_to_cpu(agpt->sizeof_partition_entry)); 532 error_found++; 533 } 534 if (le32_to_cpu(pgpt->partition_entry_array_crc32) != 535 le32_to_cpu(agpt->partition_entry_array_crc32)) { 536 pr_warn("GPT:partition_entry_array_crc32 values don't match: " 537 "0x%x != 0x%x\n", 538 le32_to_cpu(pgpt->partition_entry_array_crc32), 539 le32_to_cpu(agpt->partition_entry_array_crc32)); 540 error_found++; 541 } 542 if (le64_to_cpu(pgpt->alternate_lba) != lastlba) { 543 pr_warn("GPT:Primary header thinks Alt. header is not at the end of the disk.\n"); 544 pr_warn("GPT:%lld != %lld\n", 545 (unsigned long long)le64_to_cpu(pgpt->alternate_lba), 546 (unsigned long long)lastlba); 547 error_found++; 548 } 549 550 if (le64_to_cpu(agpt->my_lba) != lastlba) { 551 pr_warn("GPT:Alternate GPT header not at the end of the disk.\n"); 552 pr_warn("GPT:%lld != %lld\n", 553 (unsigned long long)le64_to_cpu(agpt->my_lba), 554 (unsigned long long)lastlba); 555 error_found++; 556 } 557 558 if (error_found) 559 pr_warn("GPT: Use GNU Parted to correct GPT errors.\n"); 560 return; 561 } 562 563 /** 564 * find_valid_gpt() - Search disk for valid GPT headers and PTEs 565 * @state 566 * @gpt is a GPT header ptr, filled on return. 567 * @ptes is a PTEs ptr, filled on return. 568 * Description: Returns 1 if valid, 0 on error. 569 * If valid, returns pointers to newly allocated GPT header and PTEs. 570 * Validity depends on PMBR being valid (or being overridden by the 571 * 'gpt' kernel command line option) and finding either the Primary 572 * GPT header and PTEs valid, or the Alternate GPT header and PTEs 573 * valid. If the Primary GPT header is not valid, the Alternate GPT header 574 * is not checked unless the 'gpt' kernel command line option is passed. 575 * This protects against devices which misreport their size, and forces 576 * the user to decide to use the Alternate GPT. 577 */ 578 static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt, 579 gpt_entry **ptes) 580 { 581 int good_pgpt = 0, good_agpt = 0, good_pmbr = 0; 582 gpt_header *pgpt = NULL, *agpt = NULL; 583 gpt_entry *pptes = NULL, *aptes = NULL; 584 legacy_mbr *legacymbr; 585 sector_t total_sectors = i_size_read(state->bdev->bd_inode) >> 9; 586 u64 lastlba; 587 588 if (!ptes) 589 return 0; 590 591 lastlba = last_lba(state->bdev); 592 if (!force_gpt) { 593 /* This will be added to the EFI Spec. per Intel after v1.02. */ 594 legacymbr = kzalloc(sizeof(*legacymbr), GFP_KERNEL); 595 if (!legacymbr) 596 goto fail; 597 598 read_lba(state, 0, (u8 *)legacymbr, sizeof(*legacymbr)); 599 good_pmbr = is_pmbr_valid(legacymbr, total_sectors); 600 kfree(legacymbr); 601 602 if (!good_pmbr) 603 goto fail; 604 605 pr_debug("Device has a %s MBR\n", 606 good_pmbr == GPT_MBR_PROTECTIVE ? 607 "protective" : "hybrid"); 608 } 609 610 good_pgpt = is_gpt_valid(state, GPT_PRIMARY_PARTITION_TABLE_LBA, 611 &pgpt, &pptes); 612 if (good_pgpt) 613 good_agpt = is_gpt_valid(state, 614 le64_to_cpu(pgpt->alternate_lba), 615 &agpt, &aptes); 616 if (!good_agpt && force_gpt) 617 good_agpt = is_gpt_valid(state, lastlba, &agpt, &aptes); 618 619 /* The obviously unsuccessful case */ 620 if (!good_pgpt && !good_agpt) 621 goto fail; 622 623 compare_gpts(pgpt, agpt, lastlba); 624 625 /* The good cases */ 626 if (good_pgpt) { 627 *gpt = pgpt; 628 *ptes = pptes; 629 kfree(agpt); 630 kfree(aptes); 631 if (!good_agpt) 632 pr_warn("Alternate GPT is invalid, using primary GPT.\n"); 633 return 1; 634 } 635 else if (good_agpt) { 636 *gpt = agpt; 637 *ptes = aptes; 638 kfree(pgpt); 639 kfree(pptes); 640 pr_warn("Primary GPT is invalid, using alternate GPT.\n"); 641 return 1; 642 } 643 644 fail: 645 kfree(pgpt); 646 kfree(agpt); 647 kfree(pptes); 648 kfree(aptes); 649 *gpt = NULL; 650 *ptes = NULL; 651 return 0; 652 } 653 654 /** 655 * efi_partition(struct parsed_partitions *state) 656 * @state 657 * 658 * Description: called from check.c, if the disk contains GPT 659 * partitions, sets up partition entries in the kernel. 660 * 661 * If the first block on the disk is a legacy MBR, 662 * it will get handled by msdos_partition(). 663 * If it's a Protective MBR, we'll handle it here. 664 * 665 * We do not create a Linux partition for GPT, but 666 * only for the actual data partitions. 667 * Returns: 668 * -1 if unable to read the partition table 669 * 0 if this isn't our partition table 670 * 1 if successful 671 * 672 */ 673 int efi_partition(struct parsed_partitions *state) 674 { 675 gpt_header *gpt = NULL; 676 gpt_entry *ptes = NULL; 677 u32 i; 678 unsigned ssz = bdev_logical_block_size(state->bdev) / 512; 679 680 if (!find_valid_gpt(state, &gpt, &ptes) || !gpt || !ptes) { 681 kfree(gpt); 682 kfree(ptes); 683 return 0; 684 } 685 686 pr_debug("GUID Partition Table is valid! Yea!\n"); 687 688 for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) { 689 struct partition_meta_info *info; 690 unsigned label_count = 0; 691 unsigned label_max; 692 u64 start = le64_to_cpu(ptes[i].starting_lba); 693 u64 size = le64_to_cpu(ptes[i].ending_lba) - 694 le64_to_cpu(ptes[i].starting_lba) + 1ULL; 695 696 if (!is_pte_valid(&ptes[i], last_lba(state->bdev))) 697 continue; 698 699 put_partition(state, i+1, start * ssz, size * ssz); 700 701 /* If this is a RAID volume, tell md */ 702 if (!efi_guidcmp(ptes[i].partition_type_guid, PARTITION_LINUX_RAID_GUID)) 703 state->parts[i + 1].flags = ADDPART_FLAG_RAID; 704 705 info = &state->parts[i + 1].info; 706 efi_guid_unparse(&ptes[i].unique_partition_guid, info->uuid); 707 708 /* Naively convert UTF16-LE to 7 bits. */ 709 label_max = min(sizeof(info->volname) - 1, 710 sizeof(ptes[i].partition_name)); 711 info->volname[label_max] = 0; 712 while (label_count < label_max) { 713 u8 c = ptes[i].partition_name[label_count] & 0xff; 714 if (c && !isprint(c)) 715 c = '!'; 716 info->volname[label_count] = c; 717 label_count++; 718 } 719 state->parts[i + 1].has_info = true; 720 } 721 kfree(ptes); 722 kfree(gpt); 723 strlcat(state->pp_buf, "\n", PAGE_SIZE); 724 return 1; 725 } 726