efi.c 21 KB

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