Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /************************************************************ |
| 2 | * EFI GUID Partition Table handling |
Karel Zak | 7d13af3 | 2009-11-23 09:29:13 +0100 | [diff] [blame] | 3 | * |
| 4 | * http://www.uefi.org/specs/ |
| 5 | * http://www.intel.com/technology/efi/ |
| 6 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | ************************************************************/ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | #include <linux/crc32.h> |
Will Drewry | eec7ecf | 2010-08-31 15:47:06 -0500 | [diff] [blame] | 97 | #include <linux/ctype.h> |
Karel Zak | 7d13af3 | 2009-11-23 09:29:13 +0100 | [diff] [blame] | 98 | #include <linux/math64.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 99 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 100 | #include "check.h" |
| 101 | #include "efi.h" |
| 102 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | */ |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 144 | static u64 last_lba(struct block_device *bdev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | { |
| 146 | if (!bdev || !bdev->bd_inode) |
| 147 | return 0; |
Karel Zak | 7d13af3 | 2009-11-23 09:29:13 +0100 | [diff] [blame] | 148 | return div_u64(bdev->bd_inode->i_size, |
| 149 | bdev_logical_block_size(bdev)) - 1ULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | } |
| 151 | |
| 152 | static inline int |
Olaf Hering | 4c64c30 | 2007-05-10 22:22:42 -0700 | [diff] [blame] | 153 | pmbr_part_valid(struct partition *part) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 |
Olaf Hering | 4c64c30 | 2007-05-10 22:22:42 -0700 | [diff] [blame] | 171 | is_pmbr_valid(legacy_mbr *mbr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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++) |
Olaf Hering | 4c64c30 | 2007-05-10 22:22:42 -0700 | [diff] [blame] | 177 | if (pmbr_part_valid(&mbr->partition_record[i])) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | return 1; |
| 179 | return 0; |
| 180 | } |
| 181 | |
| 182 | /** |
| 183 | * read_lba(): Read bytes from disk, starting at given LBA |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 184 | * @state |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | * @lba |
| 186 | * @buffer |
| 187 | * @size_t |
| 188 | * |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 189 | * Description: Reads @count bytes from @state->bdev into @buffer. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 190 | * Returns number of bytes read on success, 0 on error. |
| 191 | */ |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 192 | static size_t read_lba(struct parsed_partitions *state, |
| 193 | u64 lba, u8 *buffer, size_t count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | { |
| 195 | size_t totalreadcount = 0; |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 196 | struct block_device *bdev = state->bdev; |
Karel Zak | 7d13af3 | 2009-11-23 09:29:13 +0100 | [diff] [blame] | 197 | sector_t n = lba * (bdev_logical_block_size(bdev) / 512); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 199 | if (!buffer || lba > last_lba(bdev)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | return 0; |
| 201 | |
| 202 | while (count) { |
| 203 | int copied = 512; |
| 204 | Sector sect; |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 205 | unsigned char *data = read_part_sector(state, n++, §); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 221 | * @state |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | */ |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 228 | static gpt_entry *alloc_read_gpt_entries(struct parsed_partitions *state, |
| 229 | gpt_header *gpt) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | { |
| 231 | size_t count; |
| 232 | gpt_entry *pte; |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 233 | |
| 234 | if (!gpt) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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; |
Panagiotis Issaris | f8314dc | 2006-09-27 01:49:37 -0700 | [diff] [blame] | 241 | pte = kzalloc(count, GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 242 | if (!pte) |
| 243 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 245 | if (read_lba(state, le64_to_cpu(gpt->partition_entry_lba), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 257 | * @state |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | * @lba is the Logical Block Address of the partition table |
| 259 | * |
| 260 | * Description: returns GPT header on success, NULL on error. Allocates |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 261 | * and fills a GPT header starting at @ from @state->bdev. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 262 | * Note: remember to free gpt when finished with it. |
| 263 | */ |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 264 | static gpt_header *alloc_read_gpt_header(struct parsed_partitions *state, |
| 265 | u64 lba) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 266 | { |
| 267 | gpt_header *gpt; |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 268 | unsigned ssz = bdev_logical_block_size(state->bdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 269 | |
Karel Zak | 87038c2d | 2009-11-23 09:29:58 +0100 | [diff] [blame] | 270 | gpt = kzalloc(ssz, GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | if (!gpt) |
| 272 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 274 | if (read_lba(state, lba, (u8 *) gpt, ssz) < ssz) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 285 | * @state |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | */ |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 293 | static int is_gpt_valid(struct parsed_partitions *state, u64 lba, |
| 294 | gpt_header **gpt, gpt_entry **ptes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 295 | { |
| 296 | u32 crc, origcrc; |
| 297 | u64 lastlba; |
| 298 | |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 299 | if (!ptes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | return 0; |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 301 | if (!(*gpt = alloc_read_gpt_header(state, lba))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | return 0; |
| 303 | |
| 304 | /* Check the GUID Partition Table signature */ |
| 305 | if (le64_to_cpu((*gpt)->signature) != GPT_HEADER_SIGNATURE) { |
Thomas Gleixner | d991696 | 2008-07-25 01:48:26 -0700 | [diff] [blame] | 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); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | goto fail; |
| 311 | } |
| 312 | |
| 313 | /* Check the GUID Partition Table CRC */ |
| 314 | origcrc = le32_to_cpu((*gpt)->header_crc32); |
| 315 | (*gpt)->header_crc32 = 0; |
| 316 | crc = efi_crc32((const unsigned char *) (*gpt), le32_to_cpu((*gpt)->header_size)); |
| 317 | |
| 318 | if (crc != origcrc) { |
Thomas Gleixner | d991696 | 2008-07-25 01:48:26 -0700 | [diff] [blame] | 319 | pr_debug("GUID Partition Table Header CRC is wrong: %x != %x\n", |
| 320 | crc, origcrc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | goto fail; |
| 322 | } |
| 323 | (*gpt)->header_crc32 = cpu_to_le32(origcrc); |
| 324 | |
| 325 | /* Check that the my_lba entry points to the LBA that contains |
| 326 | * the GUID Partition Table */ |
| 327 | if (le64_to_cpu((*gpt)->my_lba) != lba) { |
Thomas Gleixner | d991696 | 2008-07-25 01:48:26 -0700 | [diff] [blame] | 328 | pr_debug("GPT my_lba incorrect: %lld != %lld\n", |
| 329 | (unsigned long long)le64_to_cpu((*gpt)->my_lba), |
| 330 | (unsigned long long)lba); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 331 | goto fail; |
| 332 | } |
| 333 | |
| 334 | /* Check the first_usable_lba and last_usable_lba are |
| 335 | * within the disk. |
| 336 | */ |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 337 | lastlba = last_lba(state->bdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 338 | if (le64_to_cpu((*gpt)->first_usable_lba) > lastlba) { |
Thomas Gleixner | d991696 | 2008-07-25 01:48:26 -0700 | [diff] [blame] | 339 | pr_debug("GPT: first_usable_lba incorrect: %lld > %lld\n", |
| 340 | (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba), |
| 341 | (unsigned long long)lastlba); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | goto fail; |
| 343 | } |
| 344 | if (le64_to_cpu((*gpt)->last_usable_lba) > lastlba) { |
Thomas Gleixner | d991696 | 2008-07-25 01:48:26 -0700 | [diff] [blame] | 345 | pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n", |
| 346 | (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba), |
| 347 | (unsigned long long)lastlba); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 348 | goto fail; |
| 349 | } |
| 350 | |
Timo Warns | fa039d5 | 2011-05-06 13:47:35 +0200 | [diff] [blame] | 351 | /* Check that sizeof_partition_entry has the correct value */ |
| 352 | if (le32_to_cpu((*gpt)->sizeof_partition_entry) != sizeof(gpt_entry)) { |
| 353 | pr_debug("GUID Partitition Entry Size check failed.\n"); |
| 354 | goto fail; |
| 355 | } |
| 356 | |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 357 | if (!(*ptes = alloc_read_gpt_entries(state, *gpt))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 358 | goto fail; |
| 359 | |
| 360 | /* Check the GUID Partition Entry Array CRC */ |
| 361 | crc = efi_crc32((const unsigned char *) (*ptes), |
| 362 | le32_to_cpu((*gpt)->num_partition_entries) * |
| 363 | le32_to_cpu((*gpt)->sizeof_partition_entry)); |
| 364 | |
| 365 | if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) { |
Thomas Gleixner | d991696 | 2008-07-25 01:48:26 -0700 | [diff] [blame] | 366 | pr_debug("GUID Partitition Entry Array CRC check failed.\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 367 | goto fail_ptes; |
| 368 | } |
| 369 | |
| 370 | /* We're done, all's well */ |
| 371 | return 1; |
| 372 | |
| 373 | fail_ptes: |
| 374 | kfree(*ptes); |
| 375 | *ptes = NULL; |
| 376 | fail: |
| 377 | kfree(*gpt); |
| 378 | *gpt = NULL; |
| 379 | return 0; |
| 380 | } |
| 381 | |
| 382 | /** |
| 383 | * is_pte_valid() - tests one PTE for validity |
| 384 | * @pte is the pte to check |
| 385 | * @lastlba is last lba of the disk |
| 386 | * |
| 387 | * Description: returns 1 if valid, 0 on error. |
| 388 | */ |
| 389 | static inline int |
| 390 | is_pte_valid(const gpt_entry *pte, const u64 lastlba) |
| 391 | { |
| 392 | if ((!efi_guidcmp(pte->partition_type_guid, NULL_GUID)) || |
| 393 | le64_to_cpu(pte->starting_lba) > lastlba || |
| 394 | le64_to_cpu(pte->ending_lba) > lastlba) |
| 395 | return 0; |
| 396 | return 1; |
| 397 | } |
| 398 | |
| 399 | /** |
| 400 | * compare_gpts() - Search disk for valid GPT headers and PTEs |
| 401 | * @pgpt is the primary GPT header |
| 402 | * @agpt is the alternate GPT header |
| 403 | * @lastlba is the last LBA number |
| 404 | * Description: Returns nothing. Sanity checks pgpt and agpt fields |
| 405 | * and prints warnings on discrepancies. |
| 406 | * |
| 407 | */ |
| 408 | static void |
| 409 | compare_gpts(gpt_header *pgpt, gpt_header *agpt, u64 lastlba) |
| 410 | { |
| 411 | int error_found = 0; |
| 412 | if (!pgpt || !agpt) |
| 413 | return; |
| 414 | if (le64_to_cpu(pgpt->my_lba) != le64_to_cpu(agpt->alternate_lba)) { |
| 415 | printk(KERN_WARNING |
| 416 | "GPT:Primary header LBA != Alt. header alternate_lba\n"); |
| 417 | printk(KERN_WARNING "GPT:%lld != %lld\n", |
| 418 | (unsigned long long)le64_to_cpu(pgpt->my_lba), |
| 419 | (unsigned long long)le64_to_cpu(agpt->alternate_lba)); |
| 420 | error_found++; |
| 421 | } |
| 422 | if (le64_to_cpu(pgpt->alternate_lba) != le64_to_cpu(agpt->my_lba)) { |
| 423 | printk(KERN_WARNING |
| 424 | "GPT:Primary header alternate_lba != Alt. header my_lba\n"); |
| 425 | printk(KERN_WARNING "GPT:%lld != %lld\n", |
| 426 | (unsigned long long)le64_to_cpu(pgpt->alternate_lba), |
| 427 | (unsigned long long)le64_to_cpu(agpt->my_lba)); |
| 428 | error_found++; |
| 429 | } |
| 430 | if (le64_to_cpu(pgpt->first_usable_lba) != |
| 431 | le64_to_cpu(agpt->first_usable_lba)) { |
| 432 | printk(KERN_WARNING "GPT:first_usable_lbas don't match.\n"); |
| 433 | printk(KERN_WARNING "GPT:%lld != %lld\n", |
| 434 | (unsigned long long)le64_to_cpu(pgpt->first_usable_lba), |
| 435 | (unsigned long long)le64_to_cpu(agpt->first_usable_lba)); |
| 436 | error_found++; |
| 437 | } |
| 438 | if (le64_to_cpu(pgpt->last_usable_lba) != |
| 439 | le64_to_cpu(agpt->last_usable_lba)) { |
| 440 | printk(KERN_WARNING "GPT:last_usable_lbas don't match.\n"); |
| 441 | printk(KERN_WARNING "GPT:%lld != %lld\n", |
| 442 | (unsigned long long)le64_to_cpu(pgpt->last_usable_lba), |
| 443 | (unsigned long long)le64_to_cpu(agpt->last_usable_lba)); |
| 444 | error_found++; |
| 445 | } |
| 446 | if (efi_guidcmp(pgpt->disk_guid, agpt->disk_guid)) { |
| 447 | printk(KERN_WARNING "GPT:disk_guids don't match.\n"); |
| 448 | error_found++; |
| 449 | } |
| 450 | if (le32_to_cpu(pgpt->num_partition_entries) != |
| 451 | le32_to_cpu(agpt->num_partition_entries)) { |
| 452 | printk(KERN_WARNING "GPT:num_partition_entries don't match: " |
| 453 | "0x%x != 0x%x\n", |
| 454 | le32_to_cpu(pgpt->num_partition_entries), |
| 455 | le32_to_cpu(agpt->num_partition_entries)); |
| 456 | error_found++; |
| 457 | } |
| 458 | if (le32_to_cpu(pgpt->sizeof_partition_entry) != |
| 459 | le32_to_cpu(agpt->sizeof_partition_entry)) { |
| 460 | printk(KERN_WARNING |
| 461 | "GPT:sizeof_partition_entry values don't match: " |
| 462 | "0x%x != 0x%x\n", |
| 463 | le32_to_cpu(pgpt->sizeof_partition_entry), |
| 464 | le32_to_cpu(agpt->sizeof_partition_entry)); |
| 465 | error_found++; |
| 466 | } |
| 467 | if (le32_to_cpu(pgpt->partition_entry_array_crc32) != |
| 468 | le32_to_cpu(agpt->partition_entry_array_crc32)) { |
| 469 | printk(KERN_WARNING |
| 470 | "GPT:partition_entry_array_crc32 values don't match: " |
| 471 | "0x%x != 0x%x\n", |
| 472 | le32_to_cpu(pgpt->partition_entry_array_crc32), |
| 473 | le32_to_cpu(agpt->partition_entry_array_crc32)); |
| 474 | error_found++; |
| 475 | } |
| 476 | if (le64_to_cpu(pgpt->alternate_lba) != lastlba) { |
| 477 | printk(KERN_WARNING |
| 478 | "GPT:Primary header thinks Alt. header is not at the end of the disk.\n"); |
| 479 | printk(KERN_WARNING "GPT:%lld != %lld\n", |
| 480 | (unsigned long long)le64_to_cpu(pgpt->alternate_lba), |
| 481 | (unsigned long long)lastlba); |
| 482 | error_found++; |
| 483 | } |
| 484 | |
| 485 | if (le64_to_cpu(agpt->my_lba) != lastlba) { |
| 486 | printk(KERN_WARNING |
| 487 | "GPT:Alternate GPT header not at the end of the disk.\n"); |
| 488 | printk(KERN_WARNING "GPT:%lld != %lld\n", |
| 489 | (unsigned long long)le64_to_cpu(agpt->my_lba), |
| 490 | (unsigned long long)lastlba); |
| 491 | error_found++; |
| 492 | } |
| 493 | |
| 494 | if (error_found) |
| 495 | printk(KERN_WARNING |
| 496 | "GPT: Use GNU Parted to correct GPT errors.\n"); |
| 497 | return; |
| 498 | } |
| 499 | |
| 500 | /** |
| 501 | * find_valid_gpt() - Search disk for valid GPT headers and PTEs |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 502 | * @state |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 503 | * @gpt is a GPT header ptr, filled on return. |
| 504 | * @ptes is a PTEs ptr, filled on return. |
| 505 | * Description: Returns 1 if valid, 0 on error. |
| 506 | * If valid, returns pointers to newly allocated GPT header and PTEs. |
| 507 | * Validity depends on PMBR being valid (or being overridden by the |
| 508 | * 'gpt' kernel command line option) and finding either the Primary |
| 509 | * GPT header and PTEs valid, or the Alternate GPT header and PTEs |
| 510 | * valid. If the Primary GPT header is not valid, the Alternate GPT header |
| 511 | * is not checked unless the 'gpt' kernel command line option is passed. |
| 512 | * This protects against devices which misreport their size, and forces |
| 513 | * the user to decide to use the Alternate GPT. |
| 514 | */ |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 515 | static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt, |
| 516 | gpt_entry **ptes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 517 | { |
| 518 | int good_pgpt = 0, good_agpt = 0, good_pmbr = 0; |
| 519 | gpt_header *pgpt = NULL, *agpt = NULL; |
| 520 | gpt_entry *pptes = NULL, *aptes = NULL; |
Olaf Hering | 4c64c30 | 2007-05-10 22:22:42 -0700 | [diff] [blame] | 521 | legacy_mbr *legacymbr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 522 | u64 lastlba; |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 523 | |
| 524 | if (!ptes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 525 | return 0; |
| 526 | |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 527 | lastlba = last_lba(state->bdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 528 | if (!force_gpt) { |
| 529 | /* This will be added to the EFI Spec. per Intel after v1.02. */ |
Panagiotis Issaris | f8314dc | 2006-09-27 01:49:37 -0700 | [diff] [blame] | 530 | legacymbr = kzalloc(sizeof (*legacymbr), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 531 | if (legacymbr) { |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 532 | read_lba(state, 0, (u8 *) legacymbr, |
| 533 | sizeof (*legacymbr)); |
Olaf Hering | 4c64c30 | 2007-05-10 22:22:42 -0700 | [diff] [blame] | 534 | good_pmbr = is_pmbr_valid(legacymbr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 535 | kfree(legacymbr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 536 | } |
| 537 | if (!good_pmbr) |
| 538 | goto fail; |
| 539 | } |
| 540 | |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 541 | good_pgpt = is_gpt_valid(state, GPT_PRIMARY_PARTITION_TABLE_LBA, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 542 | &pgpt, &pptes); |
| 543 | if (good_pgpt) |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 544 | good_agpt = is_gpt_valid(state, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 545 | le64_to_cpu(pgpt->alternate_lba), |
| 546 | &agpt, &aptes); |
| 547 | if (!good_agpt && force_gpt) |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 548 | good_agpt = is_gpt_valid(state, lastlba, &agpt, &aptes); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 549 | |
| 550 | /* The obviously unsuccessful case */ |
| 551 | if (!good_pgpt && !good_agpt) |
| 552 | goto fail; |
| 553 | |
| 554 | compare_gpts(pgpt, agpt, lastlba); |
| 555 | |
| 556 | /* The good cases */ |
| 557 | if (good_pgpt) { |
| 558 | *gpt = pgpt; |
| 559 | *ptes = pptes; |
| 560 | kfree(agpt); |
| 561 | kfree(aptes); |
| 562 | if (!good_agpt) { |
| 563 | printk(KERN_WARNING |
| 564 | "Alternate GPT is invalid, " |
| 565 | "using primary GPT.\n"); |
| 566 | } |
| 567 | return 1; |
| 568 | } |
| 569 | else if (good_agpt) { |
| 570 | *gpt = agpt; |
| 571 | *ptes = aptes; |
| 572 | kfree(pgpt); |
| 573 | kfree(pptes); |
| 574 | printk(KERN_WARNING |
| 575 | "Primary GPT is invalid, using alternate GPT.\n"); |
| 576 | return 1; |
| 577 | } |
| 578 | |
| 579 | fail: |
| 580 | kfree(pgpt); |
| 581 | kfree(agpt); |
| 582 | kfree(pptes); |
| 583 | kfree(aptes); |
| 584 | *gpt = NULL; |
| 585 | *ptes = NULL; |
| 586 | return 0; |
| 587 | } |
| 588 | |
| 589 | /** |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 590 | * efi_partition(struct parsed_partitions *state) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 591 | * @state |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 592 | * |
| 593 | * Description: called from check.c, if the disk contains GPT |
| 594 | * partitions, sets up partition entries in the kernel. |
| 595 | * |
| 596 | * If the first block on the disk is a legacy MBR, |
| 597 | * it will get handled by msdos_partition(). |
| 598 | * If it's a Protective MBR, we'll handle it here. |
| 599 | * |
| 600 | * We do not create a Linux partition for GPT, but |
| 601 | * only for the actual data partitions. |
| 602 | * Returns: |
| 603 | * -1 if unable to read the partition table |
| 604 | * 0 if this isn't our partition table |
| 605 | * 1 if successful |
| 606 | * |
| 607 | */ |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 608 | int efi_partition(struct parsed_partitions *state) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | { |
| 610 | gpt_header *gpt = NULL; |
| 611 | gpt_entry *ptes = NULL; |
| 612 | u32 i; |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 613 | unsigned ssz = bdev_logical_block_size(state->bdev) / 512; |
Will Drewry | eec7ecf | 2010-08-31 15:47:06 -0500 | [diff] [blame] | 614 | u8 unparsed_guid[37]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 615 | |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 616 | if (!find_valid_gpt(state, &gpt, &ptes) || !gpt || !ptes) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 617 | kfree(gpt); |
| 618 | kfree(ptes); |
| 619 | return 0; |
| 620 | } |
| 621 | |
Thomas Gleixner | d991696 | 2008-07-25 01:48:26 -0700 | [diff] [blame] | 622 | pr_debug("GUID Partition Table is valid! Yea!\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | |
| 624 | for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) { |
Will Drewry | eec7ecf | 2010-08-31 15:47:06 -0500 | [diff] [blame] | 625 | struct partition_meta_info *info; |
| 626 | unsigned label_count = 0; |
| 627 | unsigned label_max; |
Karel Zak | 7d13af3 | 2009-11-23 09:29:13 +0100 | [diff] [blame] | 628 | u64 start = le64_to_cpu(ptes[i].starting_lba); |
| 629 | u64 size = le64_to_cpu(ptes[i].ending_lba) - |
| 630 | le64_to_cpu(ptes[i].starting_lba) + 1ULL; |
| 631 | |
Tejun Heo | 1493bf2 | 2010-05-15 20:09:30 +0200 | [diff] [blame] | 632 | if (!is_pte_valid(&ptes[i], last_lba(state->bdev))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 633 | continue; |
| 634 | |
Karel Zak | 7d13af3 | 2009-11-23 09:29:13 +0100 | [diff] [blame] | 635 | put_partition(state, i+1, start * ssz, size * ssz); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 636 | |
| 637 | /* If this is a RAID volume, tell md */ |
| 638 | if (!efi_guidcmp(ptes[i].partition_type_guid, |
| 639 | PARTITION_LINUX_RAID_GUID)) |
Cesar Eduardo Barros | cc91062 | 2010-04-17 19:28:09 -0300 | [diff] [blame] | 640 | state->parts[i + 1].flags = ADDPART_FLAG_RAID; |
Will Drewry | eec7ecf | 2010-08-31 15:47:06 -0500 | [diff] [blame] | 641 | |
| 642 | info = &state->parts[i + 1].info; |
| 643 | /* Instead of doing a manual swap to big endian, reuse the |
| 644 | * common ASCII hex format as the interim. |
| 645 | */ |
| 646 | efi_guid_unparse(&ptes[i].unique_partition_guid, unparsed_guid); |
| 647 | part_pack_uuid(unparsed_guid, info->uuid); |
| 648 | |
| 649 | /* Naively convert UTF16-LE to 7 bits. */ |
| 650 | label_max = min(sizeof(info->volname) - 1, |
| 651 | sizeof(ptes[i].partition_name)); |
| 652 | info->volname[label_max] = 0; |
| 653 | while (label_count < label_max) { |
| 654 | u8 c = ptes[i].partition_name[label_count] & 0xff; |
| 655 | if (c && !isprint(c)) |
| 656 | c = '!'; |
| 657 | info->volname[label_count] = c; |
| 658 | label_count++; |
| 659 | } |
| 660 | state->parts[i + 1].has_info = true; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 661 | } |
| 662 | kfree(ptes); |
| 663 | kfree(gpt); |
Alexey Dobriyan | 9c867fb | 2010-08-10 18:03:14 -0700 | [diff] [blame] | 664 | strlcat(state->pp_buf, "\n", PAGE_SIZE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 665 | return 1; |
| 666 | } |