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
  148. pmbr_part_valid(struct partition *part)
  149. {
  150. if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
  151. le32_to_cpu(part->start_sect) == 1UL)
  152. return 1;
  153. return 0;
  154. }
  155. /**
  156. * is_pmbr_valid(): test Protective MBR for validity
  157. * @mbr: pointer to a legacy mbr structure
  158. *
  159. * Description: Returns 1 if PMBR is valid, 0 otherwise.
  160. * Validity depends on two things:
  161. * 1) MSDOS signature is in the last two bytes of the MBR
  162. * 2) One partition of type 0xEE is found
  163. */
  164. static int
  165. is_pmbr_valid(legacy_mbr *mbr)
  166. {
  167. int i;
  168. if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
  169. return 0;
  170. for (i = 0; i < 4; i++)
  171. if (pmbr_part_valid(&mbr->partition_record[i]))
  172. return 1;
  173. return 0;
  174. }
  175. /**
  176. * read_lba(): Read bytes from disk, starting at given LBA
  177. * @state
  178. * @lba
  179. * @buffer
  180. * @size_t
  181. *
  182. * Description: Reads @count bytes from @state->bdev into @buffer.
  183. * Returns number of bytes read on success, 0 on error.
  184. */
  185. static size_t read_lba(struct parsed_partitions *state,
  186. u64 lba, u8 *buffer, size_t count)
  187. {
  188. size_t totalreadcount = 0;
  189. struct block_device *bdev = state->bdev;
  190. sector_t n = lba * (bdev_logical_block_size(bdev) / 512);
  191. if (!buffer || lba > last_lba(bdev))
  192. return 0;
  193. while (count) {
  194. int copied = 512;
  195. Sector sect;
  196. unsigned char *data = read_part_sector(state, n++, &sect);
  197. if (!data)
  198. break;
  199. if (copied > count)
  200. copied = count;
  201. memcpy(buffer, data, copied);
  202. put_dev_sector(sect);
  203. buffer += copied;
  204. totalreadcount +=copied;
  205. count -= copied;
  206. }
  207. return totalreadcount;
  208. }
  209. /**
  210. * alloc_read_gpt_entries(): reads partition entries from disk
  211. * @state
  212. * @gpt - GPT header
  213. *
  214. * Description: Returns ptes on success, NULL on error.
  215. * Allocates space for PTEs based on information found in @gpt.
  216. * Notes: remember to free pte when you're done!
  217. */
  218. static gpt_entry *alloc_read_gpt_entries(struct parsed_partitions *state,
  219. gpt_header *gpt)
  220. {
  221. size_t count;
  222. gpt_entry *pte;
  223. if (!gpt)
  224. return NULL;
  225. count = le32_to_cpu(gpt->num_partition_entries) *
  226. le32_to_cpu(gpt->sizeof_partition_entry);
  227. if (!count)
  228. return NULL;
  229. pte = kmalloc(count, GFP_KERNEL);
  230. if (!pte)
  231. return NULL;
  232. if (read_lba(state, le64_to_cpu(gpt->partition_entry_lba),
  233. (u8 *) pte,
  234. count) < count) {
  235. kfree(pte);
  236. pte=NULL;
  237. return NULL;
  238. }
  239. return pte;
  240. }
  241. /**
  242. * alloc_read_gpt_header(): Allocates GPT header, reads into it from disk
  243. * @state
  244. * @lba is the Logical Block Address of the partition table
  245. *
  246. * Description: returns GPT header on success, NULL on error. Allocates
  247. * and fills a GPT header starting at @ from @state->bdev.
  248. * Note: remember to free gpt when finished with it.
  249. */
  250. static gpt_header *alloc_read_gpt_header(struct parsed_partitions *state,
  251. u64 lba)
  252. {
  253. gpt_header *gpt;
  254. unsigned ssz = bdev_logical_block_size(state->bdev);
  255. gpt = kmalloc(ssz, GFP_KERNEL);
  256. if (!gpt)
  257. return NULL;
  258. if (read_lba(state, lba, (u8 *) gpt, ssz) < ssz) {
  259. kfree(gpt);
  260. gpt=NULL;
  261. return NULL;
  262. }
  263. return gpt;
  264. }
  265. /**
  266. * is_gpt_valid() - tests one GPT header and PTEs for validity
  267. * @state
  268. * @lba is the logical block address of the GPT header to test
  269. * @gpt is a GPT header ptr, filled on return.
  270. * @ptes is a PTEs ptr, filled on return.
  271. *
  272. * Description: returns 1 if valid, 0 on error.
  273. * If valid, returns pointers to newly allocated GPT header and PTEs.
  274. */
  275. static int is_gpt_valid(struct parsed_partitions *state, u64 lba,
  276. gpt_header **gpt, gpt_entry **ptes)
  277. {
  278. u32 crc, origcrc;
  279. u64 lastlba;
  280. if (!ptes)
  281. return 0;
  282. if (!(*gpt = alloc_read_gpt_header(state, lba)))
  283. return 0;
  284. /* Check the GUID Partition Table signature */
  285. if (le64_to_cpu((*gpt)->signature) != GPT_HEADER_SIGNATURE) {
  286. pr_debug("GUID Partition Table Header signature is wrong:"
  287. "%lld != %lld\n",
  288. (unsigned long long)le64_to_cpu((*gpt)->signature),
  289. (unsigned long long)GPT_HEADER_SIGNATURE);
  290. goto fail;
  291. }
  292. /* Check the GUID Partition Table header size is too big */
  293. if (le32_to_cpu((*gpt)->header_size) >
  294. bdev_logical_block_size(state->bdev)) {
  295. pr_debug("GUID Partition Table Header size is too large: %u > %u\n",
  296. le32_to_cpu((*gpt)->header_size),
  297. bdev_logical_block_size(state->bdev));
  298. goto fail;
  299. }
  300. /* Check the GUID Partition Table header size is too small */
  301. if (le32_to_cpu((*gpt)->header_size) < sizeof(gpt_header)) {
  302. pr_debug("GUID Partition Table Header size is too small: %u < %zu\n",
  303. le32_to_cpu((*gpt)->header_size),
  304. sizeof(gpt_header));
  305. goto fail;
  306. }
  307. /* Check the GUID Partition Table CRC */
  308. origcrc = le32_to_cpu((*gpt)->header_crc32);
  309. (*gpt)->header_crc32 = 0;
  310. crc = efi_crc32((const unsigned char *) (*gpt), le32_to_cpu((*gpt)->header_size));
  311. if (crc != origcrc) {
  312. pr_debug("GUID Partition Table Header CRC is wrong: %x != %x\n",
  313. crc, origcrc);
  314. goto fail;
  315. }
  316. (*gpt)->header_crc32 = cpu_to_le32(origcrc);
  317. /* Check that the my_lba entry points to the LBA that contains
  318. * the GUID Partition Table */
  319. if (le64_to_cpu((*gpt)->my_lba) != lba) {
  320. pr_debug("GPT my_lba incorrect: %lld != %lld\n",
  321. (unsigned long long)le64_to_cpu((*gpt)->my_lba),
  322. (unsigned long long)lba);
  323. goto fail;
  324. }
  325. /* Check the first_usable_lba and last_usable_lba are
  326. * within the disk.
  327. */
  328. lastlba = last_lba(state->bdev);
  329. if (le64_to_cpu((*gpt)->first_usable_lba) > lastlba) {
  330. pr_debug("GPT: first_usable_lba incorrect: %lld > %lld\n",
  331. (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba),
  332. (unsigned long long)lastlba);
  333. goto fail;
  334. }
  335. if (le64_to_cpu((*gpt)->last_usable_lba) > lastlba) {
  336. pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n",
  337. (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba),
  338. (unsigned long long)lastlba);
  339. goto fail;
  340. }
  341. /* Check that sizeof_partition_entry has the correct value */
  342. if (le32_to_cpu((*gpt)->sizeof_partition_entry) != sizeof(gpt_entry)) {
  343. pr_debug("GUID Partitition Entry Size check failed.\n");
  344. goto fail;
  345. }
  346. if (!(*ptes = alloc_read_gpt_entries(state, *gpt)))
  347. goto fail;
  348. /* Check the GUID Partition Entry Array CRC */
  349. crc = efi_crc32((const unsigned char *) (*ptes),
  350. le32_to_cpu((*gpt)->num_partition_entries) *
  351. le32_to_cpu((*gpt)->sizeof_partition_entry));
  352. if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) {
  353. pr_debug("GUID Partitition Entry Array CRC check failed.\n");
  354. goto fail_ptes;
  355. }
  356. /* We're done, all's well */
  357. return 1;
  358. fail_ptes:
  359. kfree(*ptes);
  360. *ptes = NULL;
  361. fail:
  362. kfree(*gpt);
  363. *gpt = NULL;
  364. return 0;
  365. }
  366. /**
  367. * is_pte_valid() - tests one PTE for validity
  368. * @pte is the pte to check
  369. * @lastlba is last lba of the disk
  370. *
  371. * Description: returns 1 if valid, 0 on error.
  372. */
  373. static inline int
  374. is_pte_valid(const gpt_entry *pte, const u64 lastlba)
  375. {
  376. if ((!efi_guidcmp(pte->partition_type_guid, NULL_GUID)) ||
  377. le64_to_cpu(pte->starting_lba) > lastlba ||
  378. le64_to_cpu(pte->ending_lba) > lastlba)
  379. return 0;
  380. return 1;
  381. }
  382. /**
  383. * compare_gpts() - Search disk for valid GPT headers and PTEs
  384. * @pgpt is the primary GPT header
  385. * @agpt is the alternate GPT header
  386. * @lastlba is the last LBA number
  387. * Description: Returns nothing. Sanity checks pgpt and agpt fields
  388. * and prints warnings on discrepancies.
  389. *
  390. */
  391. static void
  392. compare_gpts(gpt_header *pgpt, gpt_header *agpt, u64 lastlba)
  393. {
  394. int error_found = 0;
  395. if (!pgpt || !agpt)
  396. return;
  397. if (le64_to_cpu(pgpt->my_lba) != le64_to_cpu(agpt->alternate_lba)) {
  398. printk(KERN_WARNING
  399. "GPT:Primary header LBA != Alt. header alternate_lba\n");
  400. printk(KERN_WARNING "GPT:%lld != %lld\n",
  401. (unsigned long long)le64_to_cpu(pgpt->my_lba),
  402. (unsigned long long)le64_to_cpu(agpt->alternate_lba));
  403. error_found++;
  404. }
  405. if (le64_to_cpu(pgpt->alternate_lba) != le64_to_cpu(agpt->my_lba)) {
  406. printk(KERN_WARNING
  407. "GPT:Primary header alternate_lba != Alt. header my_lba\n");
  408. printk(KERN_WARNING "GPT:%lld != %lld\n",
  409. (unsigned long long)le64_to_cpu(pgpt->alternate_lba),
  410. (unsigned long long)le64_to_cpu(agpt->my_lba));
  411. error_found++;
  412. }
  413. if (le64_to_cpu(pgpt->first_usable_lba) !=
  414. le64_to_cpu(agpt->first_usable_lba)) {
  415. printk(KERN_WARNING "GPT:first_usable_lbas don't match.\n");
  416. printk(KERN_WARNING "GPT:%lld != %lld\n",
  417. (unsigned long long)le64_to_cpu(pgpt->first_usable_lba),
  418. (unsigned long long)le64_to_cpu(agpt->first_usable_lba));
  419. error_found++;
  420. }
  421. if (le64_to_cpu(pgpt->last_usable_lba) !=
  422. le64_to_cpu(agpt->last_usable_lba)) {
  423. printk(KERN_WARNING "GPT:last_usable_lbas don't match.\n");
  424. printk(KERN_WARNING "GPT:%lld != %lld\n",
  425. (unsigned long long)le64_to_cpu(pgpt->last_usable_lba),
  426. (unsigned long long)le64_to_cpu(agpt->last_usable_lba));
  427. error_found++;
  428. }
  429. if (efi_guidcmp(pgpt->disk_guid, agpt->disk_guid)) {
  430. printk(KERN_WARNING "GPT:disk_guids don't match.\n");
  431. error_found++;
  432. }
  433. if (le32_to_cpu(pgpt->num_partition_entries) !=
  434. le32_to_cpu(agpt->num_partition_entries)) {
  435. printk(KERN_WARNING "GPT:num_partition_entries don't match: "
  436. "0x%x != 0x%x\n",
  437. le32_to_cpu(pgpt->num_partition_entries),
  438. le32_to_cpu(agpt->num_partition_entries));
  439. error_found++;
  440. }
  441. if (le32_to_cpu(pgpt->sizeof_partition_entry) !=
  442. le32_to_cpu(agpt->sizeof_partition_entry)) {
  443. printk(KERN_WARNING
  444. "GPT:sizeof_partition_entry values don't match: "
  445. "0x%x != 0x%x\n",
  446. le32_to_cpu(pgpt->sizeof_partition_entry),
  447. le32_to_cpu(agpt->sizeof_partition_entry));
  448. error_found++;
  449. }
  450. if (le32_to_cpu(pgpt->partition_entry_array_crc32) !=
  451. le32_to_cpu(agpt->partition_entry_array_crc32)) {
  452. printk(KERN_WARNING
  453. "GPT:partition_entry_array_crc32 values don't match: "
  454. "0x%x != 0x%x\n",
  455. le32_to_cpu(pgpt->partition_entry_array_crc32),
  456. le32_to_cpu(agpt->partition_entry_array_crc32));
  457. error_found++;
  458. }
  459. if (le64_to_cpu(pgpt->alternate_lba) != lastlba) {
  460. printk(KERN_WARNING
  461. "GPT:Primary header thinks Alt. header is not at the end of the disk.\n");
  462. printk(KERN_WARNING "GPT:%lld != %lld\n",
  463. (unsigned long long)le64_to_cpu(pgpt->alternate_lba),
  464. (unsigned long long)lastlba);
  465. error_found++;
  466. }
  467. if (le64_to_cpu(agpt->my_lba) != lastlba) {
  468. printk(KERN_WARNING
  469. "GPT:Alternate GPT header not at the end of the disk.\n");
  470. printk(KERN_WARNING "GPT:%lld != %lld\n",
  471. (unsigned long long)le64_to_cpu(agpt->my_lba),
  472. (unsigned long long)lastlba);
  473. error_found++;
  474. }
  475. if (error_found)
  476. printk(KERN_WARNING
  477. "GPT: Use GNU Parted to correct GPT errors.\n");
  478. return;
  479. }
  480. /**
  481. * find_valid_gpt() - Search disk for valid GPT headers and PTEs
  482. * @state
  483. * @gpt is a GPT header ptr, filled on return.
  484. * @ptes is a PTEs ptr, filled on return.
  485. * Description: Returns 1 if valid, 0 on error.
  486. * If valid, returns pointers to newly allocated GPT header and PTEs.
  487. * Validity depends on PMBR being valid (or being overridden by the
  488. * 'gpt' kernel command line option) and finding either the Primary
  489. * GPT header and PTEs valid, or the Alternate GPT header and PTEs
  490. * valid. If the Primary GPT header is not valid, the Alternate GPT header
  491. * is not checked unless the 'gpt' kernel command line option is passed.
  492. * This protects against devices which misreport their size, and forces
  493. * the user to decide to use the Alternate GPT.
  494. */
  495. static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt,
  496. gpt_entry **ptes)
  497. {
  498. int good_pgpt = 0, good_agpt = 0, good_pmbr = 0;
  499. gpt_header *pgpt = NULL, *agpt = NULL;
  500. gpt_entry *pptes = NULL, *aptes = NULL;
  501. legacy_mbr *legacymbr;
  502. u64 lastlba;
  503. if (!ptes)
  504. return 0;
  505. lastlba = last_lba(state->bdev);
  506. if (!force_gpt) {
  507. /* This will be added to the EFI Spec. per Intel after v1.02. */
  508. legacymbr = kzalloc(sizeof (*legacymbr), GFP_KERNEL);
  509. if (legacymbr) {
  510. read_lba(state, 0, (u8 *) legacymbr,
  511. sizeof (*legacymbr));
  512. good_pmbr = is_pmbr_valid(legacymbr);
  513. kfree(legacymbr);
  514. }
  515. if (!good_pmbr)
  516. goto fail;
  517. }
  518. good_pgpt = is_gpt_valid(state, GPT_PRIMARY_PARTITION_TABLE_LBA,
  519. &pgpt, &pptes);
  520. if (good_pgpt)
  521. good_agpt = is_gpt_valid(state,
  522. le64_to_cpu(pgpt->alternate_lba),
  523. &agpt, &aptes);
  524. if (!good_agpt && force_gpt)
  525. good_agpt = is_gpt_valid(state, lastlba, &agpt, &aptes);
  526. /* The obviously unsuccessful case */
  527. if (!good_pgpt && !good_agpt)
  528. goto fail;
  529. compare_gpts(pgpt, agpt, lastlba);
  530. /* The good cases */
  531. if (good_pgpt) {
  532. *gpt = pgpt;
  533. *ptes = pptes;
  534. kfree(agpt);
  535. kfree(aptes);
  536. if (!good_agpt) {
  537. printk(KERN_WARNING
  538. "Alternate GPT is invalid, "
  539. "using primary GPT.\n");
  540. }
  541. return 1;
  542. }
  543. else if (good_agpt) {
  544. *gpt = agpt;
  545. *ptes = aptes;
  546. kfree(pgpt);
  547. kfree(pptes);
  548. printk(KERN_WARNING
  549. "Primary GPT is invalid, using alternate GPT.\n");
  550. return 1;
  551. }
  552. fail:
  553. kfree(pgpt);
  554. kfree(agpt);
  555. kfree(pptes);
  556. kfree(aptes);
  557. *gpt = NULL;
  558. *ptes = NULL;
  559. return 0;
  560. }
  561. /**
  562. * efi_partition(struct parsed_partitions *state)
  563. * @state
  564. *
  565. * Description: called from check.c, if the disk contains GPT
  566. * partitions, sets up partition entries in the kernel.
  567. *
  568. * If the first block on the disk is a legacy MBR,
  569. * it will get handled by msdos_partition().
  570. * If it's a Protective MBR, we'll handle it here.
  571. *
  572. * We do not create a Linux partition for GPT, but
  573. * only for the actual data partitions.
  574. * Returns:
  575. * -1 if unable to read the partition table
  576. * 0 if this isn't our partition table
  577. * 1 if successful
  578. *
  579. */
  580. int efi_partition(struct parsed_partitions *state)
  581. {
  582. gpt_header *gpt = NULL;
  583. gpt_entry *ptes = NULL;
  584. u32 i;
  585. unsigned ssz = bdev_logical_block_size(state->bdev) / 512;
  586. if (!find_valid_gpt(state, &gpt, &ptes) || !gpt || !ptes) {
  587. kfree(gpt);
  588. kfree(ptes);
  589. return 0;
  590. }
  591. pr_debug("GUID Partition Table is valid! Yea!\n");
  592. for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) {
  593. struct partition_meta_info *info;
  594. unsigned label_count = 0;
  595. unsigned label_max;
  596. u64 start = le64_to_cpu(ptes[i].starting_lba);
  597. u64 size = le64_to_cpu(ptes[i].ending_lba) -
  598. le64_to_cpu(ptes[i].starting_lba) + 1ULL;
  599. if (!is_pte_valid(&ptes[i], last_lba(state->bdev)))
  600. continue;
  601. put_partition(state, i+1, start * ssz, size * ssz);
  602. /* If this is a RAID volume, tell md */
  603. if (!efi_guidcmp(ptes[i].partition_type_guid,
  604. PARTITION_LINUX_RAID_GUID))
  605. state->parts[i + 1].flags = ADDPART_FLAG_RAID;
  606. info = &state->parts[i + 1].info;
  607. efi_guid_unparse(&ptes[i].unique_partition_guid, info->uuid);
  608. /* Naively convert UTF16-LE to 7 bits. */
  609. label_max = min(sizeof(info->volname) - 1,
  610. sizeof(ptes[i].partition_name));
  611. info->volname[label_max] = 0;
  612. while (label_count < label_max) {
  613. u8 c = ptes[i].partition_name[label_count] & 0xff;
  614. if (c && !isprint(c))
  615. c = '!';
  616. info->volname[label_count] = c;
  617. label_count++;
  618. }
  619. state->parts[i + 1].has_info = true;
  620. }
  621. kfree(ptes);
  622. kfree(gpt);
  623. strlcat(state->pp_buf, "\n", PAGE_SIZE);
  624. return 1;
  625. }