fs/partitions/efi.c

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