diff options
Diffstat (limited to 'block/partitions/efi.c')
-rw-r--r-- | block/partitions/efi.c | 675 |
1 files changed, 675 insertions, 0 deletions
diff --git a/block/partitions/efi.c b/block/partitions/efi.c new file mode 100644 index 000000000000..6296b403c67a --- /dev/null +++ b/block/partitions/efi.c | |||
@@ -0,0 +1,675 @@ | |||
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 | |||
103 | /* This allows a kernel command line option 'gpt' to override | ||
104 | * the test for invalid PMBR. Not __initdata because reloading | ||
105 | * the partition tables happens after init too. | ||
106 | */ | ||
107 | static int force_gpt; | ||
108 | static int __init | ||
109 | force_gpt_fn(char *str) | ||
110 | { | ||
111 | force_gpt = 1; | ||
112 | return 1; | ||
113 | } | ||
114 | __setup("gpt", force_gpt_fn); | ||
115 | |||
116 | |||
117 | /** | ||
118 | * efi_crc32() - EFI version of crc32 function | ||
119 | * @buf: buffer to calculate crc32 of | ||
120 | * @len - length of buf | ||
121 | * | ||
122 | * Description: Returns EFI-style CRC32 value for @buf | ||
123 | * | ||
124 | * This function uses the little endian Ethernet polynomial | ||
125 | * but seeds the function with ~0, and xor's with ~0 at the end. | ||
126 | * Note, the EFI Specification, v1.02, has a reference to | ||
127 | * Dr. Dobbs Journal, May 1994 (actually it's in May 1992). | ||
128 | */ | ||
129 | static inline u32 | ||
130 | efi_crc32(const void *buf, unsigned long len) | ||
131 | { | ||
132 | return (crc32(~0L, buf, len) ^ ~0L); | ||
133 | } | ||
134 | |||
135 | /** | ||
136 | * last_lba(): return number of last logical block of device | ||
137 | * @bdev: block device | ||
138 | * | ||
139 | * Description: Returns last LBA value on success, 0 on error. | ||
140 | * This is stored (by sd and ide-geometry) in | ||
141 | * the part[0] entry for this disk, and is the number of | ||
142 | * physical sectors available on the disk. | ||
143 | */ | ||
144 | static u64 last_lba(struct block_device *bdev) | ||
145 | { | ||
146 | if (!bdev || !bdev->bd_inode) | ||
147 | return 0; | ||
148 | return div_u64(bdev->bd_inode->i_size, | ||
149 | bdev_logical_block_size(bdev)) - 1ULL; | ||
150 | } | ||
151 | |||
152 | static inline int | ||
153 | pmbr_part_valid(struct partition *part) | ||
154 | { | ||
155 | if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT && | ||
156 | le32_to_cpu(part->start_sect) == 1UL) | ||
157 | return 1; | ||
158 | return 0; | ||
159 | } | ||
160 | |||
161 | /** | ||
162 | * is_pmbr_valid(): test Protective MBR for validity | ||
163 | * @mbr: pointer to a legacy mbr structure | ||
164 | * | ||
165 | * Description: Returns 1 if PMBR is valid, 0 otherwise. | ||
166 | * Validity depends on two things: | ||
167 | * 1) MSDOS signature is in the last two bytes of the MBR | ||
168 | * 2) One partition of type 0xEE is found | ||
169 | */ | ||
170 | static int | ||
171 | is_pmbr_valid(legacy_mbr *mbr) | ||
172 | { | ||
173 | int i; | ||
174 | if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE) | ||
175 | return 0; | ||
176 | for (i = 0; i < 4; i++) | ||
177 | if (pmbr_part_valid(&mbr->partition_record[i])) | ||
178 | return 1; | ||
179 | return 0; | ||
180 | } | ||
181 | |||
182 | /** | ||
183 | * read_lba(): Read bytes from disk, starting at given LBA | ||
184 | * @state | ||
185 | * @lba | ||
186 | * @buffer | ||
187 | * @size_t | ||
188 | * | ||
189 | * Description: Reads @count bytes from @state->bdev into @buffer. | ||
190 | * Returns number of bytes read on success, 0 on error. | ||
191 | */ | ||
192 | static size_t read_lba(struct parsed_partitions *state, | ||
193 | u64 lba, u8 *buffer, size_t count) | ||
194 | { | ||
195 | size_t totalreadcount = 0; | ||
196 | struct block_device *bdev = state->bdev; | ||
197 | sector_t n = lba * (bdev_logical_block_size(bdev) / 512); | ||
198 | |||
199 | if (!buffer || lba > last_lba(bdev)) | ||
200 | return 0; | ||
201 | |||
202 | while (count) { | ||
203 | int copied = 512; | ||
204 | Sector sect; | ||
205 | unsigned char *data = read_part_sector(state, n++, §); | ||
206 | if (!data) | ||
207 | break; | ||
208 | if (copied > count) | ||
209 | copied = count; | ||
210 | memcpy(buffer, data, copied); | ||
211 | put_dev_sector(sect); | ||
212 | buffer += copied; | ||
213 | totalreadcount +=copied; | ||
214 | count -= copied; | ||
215 | } | ||
216 | return totalreadcount; | ||
217 | } | ||
218 | |||
219 | /** | ||
220 | * alloc_read_gpt_entries(): reads partition entries from disk | ||
221 | * @state | ||
222 | * @gpt - GPT header | ||
223 | * | ||
224 | * Description: Returns ptes on success, NULL on error. | ||
225 | * Allocates space for PTEs based on information found in @gpt. | ||
226 | * Notes: remember to free pte when you're done! | ||
227 | */ | ||
228 | static gpt_entry *alloc_read_gpt_entries(struct parsed_partitions *state, | ||
229 | gpt_header *gpt) | ||
230 | { | ||
231 | size_t count; | ||
232 | gpt_entry *pte; | ||
233 | |||
234 | if (!gpt) | ||
235 | return NULL; | ||
236 | |||
237 | count = le32_to_cpu(gpt->num_partition_entries) * | ||
238 | le32_to_cpu(gpt->sizeof_partition_entry); | ||
239 | if (!count) | ||
240 | return NULL; | ||
241 | pte = kzalloc(count, GFP_KERNEL); | ||
242 | if (!pte) | ||
243 | return NULL; | ||
244 | |||
245 | if (read_lba(state, le64_to_cpu(gpt->partition_entry_lba), | ||
246 | (u8 *) pte, | ||
247 | count) < count) { | ||
248 | kfree(pte); | ||
249 | pte=NULL; | ||
250 | return NULL; | ||
251 | } | ||
252 | return pte; | ||
253 | } | ||
254 | |||
255 | /** | ||
256 | * alloc_read_gpt_header(): Allocates GPT header, reads into it from disk | ||
257 | * @state | ||
258 | * @lba is the Logical Block Address of the partition table | ||
259 | * | ||
260 | * Description: returns GPT header on success, NULL on error. Allocates | ||
261 | * and fills a GPT header starting at @ from @state->bdev. | ||
262 | * Note: remember to free gpt when finished with it. | ||
263 | */ | ||
264 | static gpt_header *alloc_read_gpt_header(struct parsed_partitions *state, | ||
265 | u64 lba) | ||
266 | { | ||
267 | gpt_header *gpt; | ||
268 | unsigned ssz = bdev_logical_block_size(state->bdev); | ||
269 | |||
270 | gpt = kzalloc(ssz, GFP_KERNEL); | ||
271 | if (!gpt) | ||
272 | return NULL; | ||
273 | |||
274 | if (read_lba(state, lba, (u8 *) gpt, ssz) < ssz) { | ||
275 | kfree(gpt); | ||
276 | gpt=NULL; | ||
277 | return NULL; | ||
278 | } | ||
279 | |||
280 | return gpt; | ||
281 | } | ||
282 | |||
283 | /** | ||
284 | * is_gpt_valid() - tests one GPT header and PTEs for validity | ||
285 | * @state | ||
286 | * @lba is the logical block address of the GPT header to test | ||
287 | * @gpt is a GPT header ptr, filled on return. | ||
288 | * @ptes is a PTEs ptr, filled on return. | ||
289 | * | ||
290 | * Description: returns 1 if valid, 0 on error. | ||
291 | * If valid, returns pointers to newly allocated GPT header and PTEs. | ||
292 | */ | ||
293 | static int is_gpt_valid(struct parsed_partitions *state, u64 lba, | ||
294 | gpt_header **gpt, gpt_entry **ptes) | ||
295 | { | ||
296 | u32 crc, origcrc; | ||
297 | u64 lastlba; | ||
298 | |||
299 | if (!ptes) | ||
300 | return 0; | ||
301 | if (!(*gpt = alloc_read_gpt_header(state, lba))) | ||
302 | return 0; | ||
303 | |||
304 | /* Check the GUID Partition Table signature */ | ||
305 | if (le64_to_cpu((*gpt)->signature) != GPT_HEADER_SIGNATURE) { | ||
306 | pr_debug("GUID Partition Table Header signature is wrong:" | ||
307 | "%lld != %lld\n", | ||
308 | (unsigned long long)le64_to_cpu((*gpt)->signature), | ||
309 | (unsigned long long)GPT_HEADER_SIGNATURE); | ||
310 | goto fail; | ||
311 | } | ||
312 | |||
313 | /* Check the GUID Partition Table header size */ | ||
314 | if (le32_to_cpu((*gpt)->header_size) > | ||
315 | bdev_logical_block_size(state->bdev)) { | ||
316 | pr_debug("GUID Partition Table Header size is wrong: %u > %u\n", | ||
317 | le32_to_cpu((*gpt)->header_size), | ||
318 | bdev_logical_block_size(state->bdev)); | ||
319 | goto fail; | ||
320 | } | ||
321 | |||
322 | /* Check the GUID Partition Table CRC */ | ||
323 | origcrc = le32_to_cpu((*gpt)->header_crc32); | ||
324 | (*gpt)->header_crc32 = 0; | ||
325 | crc = efi_crc32((const unsigned char *) (*gpt), le32_to_cpu((*gpt)->header_size)); | ||
326 | |||
327 | if (crc != origcrc) { | ||
328 | pr_debug("GUID Partition Table Header CRC is wrong: %x != %x\n", | ||
329 | crc, origcrc); | ||
330 | goto fail; | ||
331 | } | ||
332 | (*gpt)->header_crc32 = cpu_to_le32(origcrc); | ||
333 | |||
334 | /* Check that the my_lba entry points to the LBA that contains | ||
335 | * the GUID Partition Table */ | ||
336 | if (le64_to_cpu((*gpt)->my_lba) != lba) { | ||
337 | pr_debug("GPT my_lba incorrect: %lld != %lld\n", | ||
338 | (unsigned long long)le64_to_cpu((*gpt)->my_lba), | ||
339 | (unsigned long long)lba); | ||
340 | goto fail; | ||
341 | } | ||
342 | |||
343 | /* Check the first_usable_lba and last_usable_lba are | ||
344 | * within the disk. | ||
345 | */ | ||
346 | lastlba = last_lba(state->bdev); | ||
347 | if (le64_to_cpu((*gpt)->first_usable_lba) > lastlba) { | ||
348 | pr_debug("GPT: first_usable_lba incorrect: %lld > %lld\n", | ||
349 | (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba), | ||
350 | (unsigned long long)lastlba); | ||
351 | goto fail; | ||
352 | } | ||
353 | if (le64_to_cpu((*gpt)->last_usable_lba) > lastlba) { | ||
354 | pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n", | ||
355 | (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba), | ||
356 | (unsigned long long)lastlba); | ||
357 | goto fail; | ||
358 | } | ||
359 | |||
360 | /* Check that sizeof_partition_entry has the correct value */ | ||
361 | if (le32_to_cpu((*gpt)->sizeof_partition_entry) != sizeof(gpt_entry)) { | ||
362 | pr_debug("GUID Partitition Entry Size check failed.\n"); | ||
363 | goto fail; | ||
364 | } | ||
365 | |||
366 | if (!(*ptes = alloc_read_gpt_entries(state, *gpt))) | ||
367 | goto fail; | ||
368 | |||
369 | /* Check the GUID Partition Entry Array CRC */ | ||
370 | crc = efi_crc32((const unsigned char *) (*ptes), | ||
371 | le32_to_cpu((*gpt)->num_partition_entries) * | ||
372 | le32_to_cpu((*gpt)->sizeof_partition_entry)); | ||
373 | |||
374 | if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) { | ||
375 | pr_debug("GUID Partitition Entry Array CRC check failed.\n"); | ||
376 | goto fail_ptes; | ||
377 | } | ||
378 | |||
379 | /* We're done, all's well */ | ||
380 | return 1; | ||
381 | |||
382 | fail_ptes: | ||
383 | kfree(*ptes); | ||
384 | *ptes = NULL; | ||
385 | fail: | ||
386 | kfree(*gpt); | ||
387 | *gpt = NULL; | ||
388 | return 0; | ||
389 | } | ||
390 | |||
391 | /** | ||
392 | * is_pte_valid() - tests one PTE for validity | ||
393 | * @pte is the pte to check | ||
394 | * @lastlba is last lba of the disk | ||
395 | * | ||
396 | * Description: returns 1 if valid, 0 on error. | ||
397 | */ | ||
398 | static inline int | ||
399 | is_pte_valid(const gpt_entry *pte, const u64 lastlba) | ||
400 | { | ||
401 | if ((!efi_guidcmp(pte->partition_type_guid, NULL_GUID)) || | ||
402 | le64_to_cpu(pte->starting_lba) > lastlba || | ||
403 | le64_to_cpu(pte->ending_lba) > lastlba) | ||
404 | return 0; | ||
405 | return 1; | ||
406 | } | ||
407 | |||
408 | /** | ||
409 | * compare_gpts() - Search disk for valid GPT headers and PTEs | ||
410 | * @pgpt is the primary GPT header | ||
411 | * @agpt is the alternate GPT header | ||
412 | * @lastlba is the last LBA number | ||
413 | * Description: Returns nothing. Sanity checks pgpt and agpt fields | ||
414 | * and prints warnings on discrepancies. | ||
415 | * | ||
416 | */ | ||
417 | static void | ||
418 | compare_gpts(gpt_header *pgpt, gpt_header *agpt, u64 lastlba) | ||
419 | { | ||
420 | int error_found = 0; | ||
421 | if (!pgpt || !agpt) | ||
422 | return; | ||
423 | if (le64_to_cpu(pgpt->my_lba) != le64_to_cpu(agpt->alternate_lba)) { | ||
424 | printk(KERN_WARNING | ||
425 | "GPT:Primary header LBA != Alt. header alternate_lba\n"); | ||
426 | printk(KERN_WARNING "GPT:%lld != %lld\n", | ||
427 | (unsigned long long)le64_to_cpu(pgpt->my_lba), | ||
428 | (unsigned long long)le64_to_cpu(agpt->alternate_lba)); | ||
429 | error_found++; | ||
430 | } | ||
431 | if (le64_to_cpu(pgpt->alternate_lba) != le64_to_cpu(agpt->my_lba)) { | ||
432 | printk(KERN_WARNING | ||
433 | "GPT:Primary header alternate_lba != Alt. header my_lba\n"); | ||
434 | printk(KERN_WARNING "GPT:%lld != %lld\n", | ||
435 | (unsigned long long)le64_to_cpu(pgpt->alternate_lba), | ||
436 | (unsigned long long)le64_to_cpu(agpt->my_lba)); | ||
437 | error_found++; | ||
438 | } | ||
439 | if (le64_to_cpu(pgpt->first_usable_lba) != | ||
440 | le64_to_cpu(agpt->first_usable_lba)) { | ||
441 | printk(KERN_WARNING "GPT:first_usable_lbas don't match.\n"); | ||
442 | printk(KERN_WARNING "GPT:%lld != %lld\n", | ||
443 | (unsigned long long)le64_to_cpu(pgpt->first_usable_lba), | ||
444 | (unsigned long long)le64_to_cpu(agpt->first_usable_lba)); | ||
445 | error_found++; | ||
446 | } | ||
447 | if (le64_to_cpu(pgpt->last_usable_lba) != | ||
448 | le64_to_cpu(agpt->last_usable_lba)) { | ||
449 | printk(KERN_WARNING "GPT:last_usable_lbas don't match.\n"); | ||
450 | printk(KERN_WARNING "GPT:%lld != %lld\n", | ||
451 | (unsigned long long)le64_to_cpu(pgpt->last_usable_lba), | ||
452 | (unsigned long long)le64_to_cpu(agpt->last_usable_lba)); | ||
453 | error_found++; | ||
454 | } | ||
455 | if (efi_guidcmp(pgpt->disk_guid, agpt->disk_guid)) { | ||
456 | printk(KERN_WARNING "GPT:disk_guids don't match.\n"); | ||
457 | error_found++; | ||
458 | } | ||
459 | if (le32_to_cpu(pgpt->num_partition_entries) != | ||
460 | le32_to_cpu(agpt->num_partition_entries)) { | ||
461 | printk(KERN_WARNING "GPT:num_partition_entries don't match: " | ||
462 | "0x%x != 0x%x\n", | ||
463 | le32_to_cpu(pgpt->num_partition_entries), | ||
464 | le32_to_cpu(agpt->num_partition_entries)); | ||
465 | error_found++; | ||
466 | } | ||
467 | if (le32_to_cpu(pgpt->sizeof_partition_entry) != | ||
468 | le32_to_cpu(agpt->sizeof_partition_entry)) { | ||
469 | printk(KERN_WARNING | ||
470 | "GPT:sizeof_partition_entry values don't match: " | ||
471 | "0x%x != 0x%x\n", | ||
472 | le32_to_cpu(pgpt->sizeof_partition_entry), | ||
473 | le32_to_cpu(agpt->sizeof_partition_entry)); | ||
474 | error_found++; | ||
475 | } | ||
476 | if (le32_to_cpu(pgpt->partition_entry_array_crc32) != | ||
477 | le32_to_cpu(agpt->partition_entry_array_crc32)) { | ||
478 | printk(KERN_WARNING | ||
479 | "GPT:partition_entry_array_crc32 values don't match: " | ||
480 | "0x%x != 0x%x\n", | ||
481 | le32_to_cpu(pgpt->partition_entry_array_crc32), | ||
482 | le32_to_cpu(agpt->partition_entry_array_crc32)); | ||
483 | error_found++; | ||
484 | } | ||
485 | if (le64_to_cpu(pgpt->alternate_lba) != lastlba) { | ||
486 | printk(KERN_WARNING | ||
487 | "GPT:Primary header thinks Alt. header is not at the end of the disk.\n"); | ||
488 | printk(KERN_WARNING "GPT:%lld != %lld\n", | ||
489 | (unsigned long long)le64_to_cpu(pgpt->alternate_lba), | ||
490 | (unsigned long long)lastlba); | ||
491 | error_found++; | ||
492 | } | ||
493 | |||
494 | if (le64_to_cpu(agpt->my_lba) != lastlba) { | ||
495 | printk(KERN_WARNING | ||
496 | "GPT:Alternate GPT header not at the end of the disk.\n"); | ||
497 | printk(KERN_WARNING "GPT:%lld != %lld\n", | ||
498 | (unsigned long long)le64_to_cpu(agpt->my_lba), | ||
499 | (unsigned long long)lastlba); | ||
500 | error_found++; | ||
501 | } | ||
502 | |||
503 | if (error_found) | ||
504 | printk(KERN_WARNING | ||
505 | "GPT: Use GNU Parted to correct GPT errors.\n"); | ||
506 | return; | ||
507 | } | ||
508 | |||
509 | /** | ||
510 | * find_valid_gpt() - Search disk for valid GPT headers and PTEs | ||
511 | * @state | ||
512 | * @gpt is a GPT header ptr, filled on return. | ||
513 | * @ptes is a PTEs ptr, filled on return. | ||
514 | * Description: Returns 1 if valid, 0 on error. | ||
515 | * If valid, returns pointers to newly allocated GPT header and PTEs. | ||
516 | * Validity depends on PMBR being valid (or being overridden by the | ||
517 | * 'gpt' kernel command line option) and finding either the Primary | ||
518 | * GPT header and PTEs valid, or the Alternate GPT header and PTEs | ||
519 | * valid. If the Primary GPT header is not valid, the Alternate GPT header | ||
520 | * is not checked unless the 'gpt' kernel command line option is passed. | ||
521 | * This protects against devices which misreport their size, and forces | ||
522 | * the user to decide to use the Alternate GPT. | ||
523 | */ | ||
524 | static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt, | ||
525 | gpt_entry **ptes) | ||
526 | { | ||
527 | int good_pgpt = 0, good_agpt = 0, good_pmbr = 0; | ||
528 | gpt_header *pgpt = NULL, *agpt = NULL; | ||
529 | gpt_entry *pptes = NULL, *aptes = NULL; | ||
530 | legacy_mbr *legacymbr; | ||
531 | u64 lastlba; | ||
532 | |||
533 | if (!ptes) | ||
534 | return 0; | ||
535 | |||
536 | lastlba = last_lba(state->bdev); | ||
537 | if (!force_gpt) { | ||
538 | /* This will be added to the EFI Spec. per Intel after v1.02. */ | ||
539 | legacymbr = kzalloc(sizeof (*legacymbr), GFP_KERNEL); | ||
540 | if (legacymbr) { | ||
541 | read_lba(state, 0, (u8 *) legacymbr, | ||
542 | sizeof (*legacymbr)); | ||
543 | good_pmbr = is_pmbr_valid(legacymbr); | ||
544 | kfree(legacymbr); | ||
545 | } | ||
546 | if (!good_pmbr) | ||
547 | goto fail; | ||
548 | } | ||
549 | |||
550 | good_pgpt = is_gpt_valid(state, GPT_PRIMARY_PARTITION_TABLE_LBA, | ||
551 | &pgpt, &pptes); | ||
552 | if (good_pgpt) | ||
553 | good_agpt = is_gpt_valid(state, | ||
554 | le64_to_cpu(pgpt->alternate_lba), | ||
555 | &agpt, &aptes); | ||
556 | if (!good_agpt && force_gpt) | ||
557 | good_agpt = is_gpt_valid(state, lastlba, &agpt, &aptes); | ||
558 | |||
559 | /* The obviously unsuccessful case */ | ||
560 | if (!good_pgpt && !good_agpt) | ||
561 | goto fail; | ||
562 | |||
563 | compare_gpts(pgpt, agpt, lastlba); | ||
564 | |||
565 | /* The good cases */ | ||
566 | if (good_pgpt) { | ||
567 | *gpt = pgpt; | ||
568 | *ptes = pptes; | ||
569 | kfree(agpt); | ||
570 | kfree(aptes); | ||
571 | if (!good_agpt) { | ||
572 | printk(KERN_WARNING | ||
573 | "Alternate GPT is invalid, " | ||
574 | "using primary GPT.\n"); | ||
575 | } | ||
576 | return 1; | ||
577 | } | ||
578 | else if (good_agpt) { | ||
579 | *gpt = agpt; | ||
580 | *ptes = aptes; | ||
581 | kfree(pgpt); | ||
582 | kfree(pptes); | ||
583 | printk(KERN_WARNING | ||
584 | "Primary GPT is invalid, using alternate GPT.\n"); | ||
585 | return 1; | ||
586 | } | ||
587 | |||
588 | fail: | ||
589 | kfree(pgpt); | ||
590 | kfree(agpt); | ||
591 | kfree(pptes); | ||
592 | kfree(aptes); | ||
593 | *gpt = NULL; | ||
594 | *ptes = NULL; | ||
595 | return 0; | ||
596 | } | ||
597 | |||
598 | /** | ||
599 | * efi_partition(struct parsed_partitions *state) | ||
600 | * @state | ||
601 | * | ||
602 | * Description: called from check.c, if the disk contains GPT | ||
603 | * partitions, sets up partition entries in the kernel. | ||
604 | * | ||
605 | * If the first block on the disk is a legacy MBR, | ||
606 | * it will get handled by msdos_partition(). | ||
607 | * If it's a Protective MBR, we'll handle it here. | ||
608 | * | ||
609 | * We do not create a Linux partition for GPT, but | ||
610 | * only for the actual data partitions. | ||
611 | * Returns: | ||
612 | * -1 if unable to read the partition table | ||
613 | * 0 if this isn't our partition table | ||
614 | * 1 if successful | ||
615 | * | ||
616 | */ | ||
617 | int efi_partition(struct parsed_partitions *state) | ||
618 | { | ||
619 | gpt_header *gpt = NULL; | ||
620 | gpt_entry *ptes = NULL; | ||
621 | u32 i; | ||
622 | unsigned ssz = bdev_logical_block_size(state->bdev) / 512; | ||
623 | u8 unparsed_guid[37]; | ||
624 | |||
625 | if (!find_valid_gpt(state, &gpt, &ptes) || !gpt || !ptes) { | ||
626 | kfree(gpt); | ||
627 | kfree(ptes); | ||
628 | return 0; | ||
629 | } | ||
630 | |||
631 | pr_debug("GUID Partition Table is valid! Yea!\n"); | ||
632 | |||
633 | for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) { | ||
634 | struct partition_meta_info *info; | ||
635 | unsigned label_count = 0; | ||
636 | unsigned label_max; | ||
637 | u64 start = le64_to_cpu(ptes[i].starting_lba); | ||
638 | u64 size = le64_to_cpu(ptes[i].ending_lba) - | ||
639 | le64_to_cpu(ptes[i].starting_lba) + 1ULL; | ||
640 | |||
641 | if (!is_pte_valid(&ptes[i], last_lba(state->bdev))) | ||
642 | continue; | ||
643 | |||
644 | put_partition(state, i+1, start * ssz, size * ssz); | ||
645 | |||
646 | /* If this is a RAID volume, tell md */ | ||
647 | if (!efi_guidcmp(ptes[i].partition_type_guid, | ||
648 | PARTITION_LINUX_RAID_GUID)) | ||
649 | state->parts[i + 1].flags = ADDPART_FLAG_RAID; | ||
650 | |||
651 | info = &state->parts[i + 1].info; | ||
652 | /* Instead of doing a manual swap to big endian, reuse the | ||
653 | * common ASCII hex format as the interim. | ||
654 | */ | ||
655 | efi_guid_unparse(&ptes[i].unique_partition_guid, unparsed_guid); | ||
656 | part_pack_uuid(unparsed_guid, info->uuid); | ||
657 | |||
658 | /* Naively convert UTF16-LE to 7 bits. */ | ||
659 | label_max = min(sizeof(info->volname) - 1, | ||
660 | sizeof(ptes[i].partition_name)); | ||
661 | info->volname[label_max] = 0; | ||
662 | while (label_count < label_max) { | ||
663 | u8 c = ptes[i].partition_name[label_count] & 0xff; | ||
664 | if (c && !isprint(c)) | ||
665 | c = '!'; | ||
666 | info->volname[label_count] = c; | ||
667 | label_count++; | ||
668 | } | ||
669 | state->parts[i + 1].has_info = true; | ||
670 | } | ||
671 | kfree(ptes); | ||
672 | kfree(gpt); | ||
673 | strlcat(state->pp_buf, "\n", PAGE_SIZE); | ||
674 | return 1; | ||
675 | } | ||