From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- block/partitions/efi.c | 757 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 757 insertions(+) create mode 100644 block/partitions/efi.c (limited to 'block/partitions/efi.c') diff --git a/block/partitions/efi.c b/block/partitions/efi.c new file mode 100644 index 000000000..5e9be13a5 --- /dev/null +++ b/block/partitions/efi.c @@ -0,0 +1,757 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/************************************************************ + * EFI GUID Partition Table handling + * + * http://www.uefi.org/specs/ + * http://www.intel.com/technology/efi/ + * + * efi.[ch] by Matt Domsch + * Copyright 2000,2001,2002,2004 Dell Inc. + * + * TODO: + * + * Changelog: + * Mon August 5th, 2013 Davidlohr Bueso + * - detect hybrid MBRs, tighter pMBR checking & cleanups. + * + * Mon Nov 09 2004 Matt Domsch + * - test for valid PMBR and valid PGPT before ever reading + * AGPT, allow override with 'gpt' kernel command line option. + * - check for first/last_usable_lba outside of size of disk + * + * Tue Mar 26 2002 Matt Domsch + * - Ported to 2.5.7-pre1 and 2.5.7-dj2 + * - Applied patch to avoid fault in alternate header handling + * - cleaned up find_valid_gpt + * - On-disk structure and copy in memory is *always* LE now - + * swab fields as needed + * - remove print_gpt_header() + * - only use first max_p partition entries, to keep the kernel minor number + * and partition numbers tied. + * + * Mon Feb 04 2002 Matt Domsch + * - Removed __PRIPTR_PREFIX - not being used + * + * Mon Jan 14 2002 Matt Domsch + * - Ported to 2.5.2-pre11 + library crc32 patch Linus applied + * + * Thu Dec 6 2001 Matt Domsch + * - Added compare_gpts(). + * - moved le_efi_guid_to_cpus() back into this file. GPT is the only + * thing that keeps EFI GUIDs on disk. + * - Changed gpt structure names and members to be simpler and more Linux-like. + * + * Wed Oct 17 2001 Matt Domsch + * - Removed CONFIG_DEVFS_VOLUMES_UUID code entirely per Martin Wilck + * + * Wed Oct 10 2001 Matt Domsch + * - Changed function comments to DocBook style per Andreas Dilger suggestion. + * + * Mon Oct 08 2001 Matt Domsch + * - Change read_lba() to use the page cache per Al Viro's work. + * - print u64s properly on all architectures + * - fixed debug_printk(), now Dprintk() + * + * Mon Oct 01 2001 Matt Domsch + * - Style cleanups + * - made most functions static + * - Endianness addition + * - remove test for second alternate header, as it's not per spec, + * and is unnecessary. There's now a method to read/write the last + * sector of an odd-sized disk from user space. No tools have ever + * been released which used this code, so it's effectively dead. + * - Per Asit Mallick of Intel, added a test for a valid PMBR. + * - Added kernel command line option 'gpt' to override valid PMBR test. + * + * Wed Jun 6 2001 Martin Wilck + * - added devfs volume UUID support (/dev/volumes/uuids) for + * mounting file systems by the partition GUID. + * + * Tue Dec 5 2000 Matt Domsch + * - Moved crc32() to linux/lib, added efi_crc32(). + * + * Thu Nov 30 2000 Matt Domsch + * - Replaced Intel's CRC32 function with an equivalent + * non-license-restricted version. + * + * Wed Oct 25 2000 Matt Domsch + * - Fixed the last_lba() call to return the proper last block + * + * Thu Oct 12 2000 Matt Domsch + * - Thanks to Andries Brouwer for his debugging assistance. + * - Code works, detects all the partitions. + * + ************************************************************/ +#include +#include +#include +#include +#include +#include "check.h" +#include "efi.h" + +/* This allows a kernel command line option 'gpt' to override + * the test for invalid PMBR. Not __initdata because reloading + * the partition tables happens after init too. + */ +static int force_gpt; +static int __init +force_gpt_fn(char *str) +{ + force_gpt = 1; + return 1; +} +__setup("gpt", force_gpt_fn); + + +/** + * efi_crc32() - EFI version of crc32 function + * @buf: buffer to calculate crc32 of + * @len: length of buf + * + * Description: Returns EFI-style CRC32 value for @buf + * + * This function uses the little endian Ethernet polynomial + * but seeds the function with ~0, and xor's with ~0 at the end. + * Note, the EFI Specification, v1.02, has a reference to + * Dr. Dobbs Journal, May 1994 (actually it's in May 1992). + */ +static inline u32 +efi_crc32(const void *buf, unsigned long len) +{ + return (crc32(~0L, buf, len) ^ ~0L); +} + +/** + * last_lba(): return number of last logical block of device + * @disk: block device + * + * Description: Returns last LBA value on success, 0 on error. + * This is stored (by sd and ide-geometry) in + * the part[0] entry for this disk, and is the number of + * physical sectors available on the disk. + */ +static u64 last_lba(struct gendisk *disk) +{ + return div_u64(bdev_nr_bytes(disk->part0), + queue_logical_block_size(disk->queue)) - 1ULL; +} + +static inline int pmbr_part_valid(gpt_mbr_record *part) +{ + if (part->os_type != EFI_PMBR_OSTYPE_EFI_GPT) + goto invalid; + + /* set to 0x00000001 (i.e., the LBA of the GPT Partition Header) */ + if (le32_to_cpu(part->starting_lba) != GPT_PRIMARY_PARTITION_TABLE_LBA) + goto invalid; + + return GPT_MBR_PROTECTIVE; +invalid: + return 0; +} + +/** + * is_pmbr_valid(): test Protective MBR for validity + * @mbr: pointer to a legacy mbr structure + * @total_sectors: amount of sectors in the device + * + * Description: Checks for a valid protective or hybrid + * master boot record (MBR). The validity of a pMBR depends + * on all of the following properties: + * 1) MSDOS signature is in the last two bytes of the MBR + * 2) One partition of type 0xEE is found + * + * In addition, a hybrid MBR will have up to three additional + * primary partitions, which point to the same space that's + * marked out by up to three GPT partitions. + * + * Returns 0 upon invalid MBR, or GPT_MBR_PROTECTIVE or + * GPT_MBR_HYBRID depending on the device layout. + */ +static int is_pmbr_valid(legacy_mbr *mbr, sector_t total_sectors) +{ + uint32_t sz = 0; + int i, part = 0, ret = 0; /* invalid by default */ + + if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE) + goto done; + + for (i = 0; i < 4; i++) { + ret = pmbr_part_valid(&mbr->partition_record[i]); + if (ret == GPT_MBR_PROTECTIVE) { + part = i; + /* + * Ok, we at least know that there's a protective MBR, + * now check if there are other partition types for + * hybrid MBR. + */ + goto check_hybrid; + } + } + + if (ret != GPT_MBR_PROTECTIVE) + goto done; +check_hybrid: + for (i = 0; i < 4; i++) + if ((mbr->partition_record[i].os_type != + EFI_PMBR_OSTYPE_EFI_GPT) && + (mbr->partition_record[i].os_type != 0x00)) + ret = GPT_MBR_HYBRID; + + /* + * Protective MBRs take up the lesser of the whole disk + * or 2 TiB (32bit LBA), ignoring the rest of the disk. + * Some partitioning programs, nonetheless, choose to set + * the size to the maximum 32-bit limitation, disregarding + * the disk size. + * + * Hybrid MBRs do not necessarily comply with this. + * + * Consider a bad value here to be a warning to support dd'ing + * an image from a smaller disk to a larger disk. + */ + if (ret == GPT_MBR_PROTECTIVE) { + sz = le32_to_cpu(mbr->partition_record[part].size_in_lba); + if (sz != (uint32_t) total_sectors - 1 && sz != 0xFFFFFFFF) + pr_debug("GPT: mbr size in lba (%u) different than whole disk (%u).\n", + sz, min_t(uint32_t, + total_sectors - 1, 0xFFFFFFFF)); + } +done: + return ret; +} + +/** + * read_lba(): Read bytes from disk, starting at given LBA + * @state: disk parsed partitions + * @lba: the Logical Block Address of the partition table + * @buffer: destination buffer + * @count: bytes to read + * + * Description: Reads @count bytes from @state->disk into @buffer. + * Returns number of bytes read on success, 0 on error. + */ +static size_t read_lba(struct parsed_partitions *state, + u64 lba, u8 *buffer, size_t count) +{ + size_t totalreadcount = 0; + sector_t n = lba * + (queue_logical_block_size(state->disk->queue) / 512); + + if (!buffer || lba > last_lba(state->disk)) + return 0; + + while (count) { + int copied = 512; + Sector sect; + unsigned char *data = read_part_sector(state, n++, §); + if (!data) + break; + if (copied > count) + copied = count; + memcpy(buffer, data, copied); + put_dev_sector(sect); + buffer += copied; + totalreadcount +=copied; + count -= copied; + } + return totalreadcount; +} + +/** + * alloc_read_gpt_entries(): reads partition entries from disk + * @state: disk parsed partitions + * @gpt: GPT header + * + * Description: Returns ptes on success, NULL on error. + * Allocates space for PTEs based on information found in @gpt. + * Notes: remember to free pte when you're done! + */ +static gpt_entry *alloc_read_gpt_entries(struct parsed_partitions *state, + gpt_header *gpt) +{ + size_t count; + gpt_entry *pte; + + if (!gpt) + return NULL; + + count = (size_t)le32_to_cpu(gpt->num_partition_entries) * + le32_to_cpu(gpt->sizeof_partition_entry); + if (!count) + return NULL; + pte = kmalloc(count, GFP_KERNEL); + if (!pte) + return NULL; + + if (read_lba(state, le64_to_cpu(gpt->partition_entry_lba), + (u8 *) pte, count) < count) { + kfree(pte); + pte=NULL; + return NULL; + } + return pte; +} + +/** + * alloc_read_gpt_header(): Allocates GPT header, reads into it from disk + * @state: disk parsed partitions + * @lba: the Logical Block Address of the partition table + * + * Description: returns GPT header on success, NULL on error. Allocates + * and fills a GPT header starting at @ from @state->disk. + * Note: remember to free gpt when finished with it. + */ +static gpt_header *alloc_read_gpt_header(struct parsed_partitions *state, + u64 lba) +{ + gpt_header *gpt; + unsigned ssz = queue_logical_block_size(state->disk->queue); + + gpt = kmalloc(ssz, GFP_KERNEL); + if (!gpt) + return NULL; + + if (read_lba(state, lba, (u8 *) gpt, ssz) < ssz) { + kfree(gpt); + gpt=NULL; + return NULL; + } + + return gpt; +} + +/** + * is_gpt_valid() - tests one GPT header and PTEs for validity + * @state: disk parsed partitions + * @lba: logical block address of the GPT header to test + * @gpt: GPT header ptr, filled on return. + * @ptes: PTEs ptr, filled on return. + * + * Description: returns 1 if valid, 0 on error. + * If valid, returns pointers to newly allocated GPT header and PTEs. + */ +static int is_gpt_valid(struct parsed_partitions *state, u64 lba, + gpt_header **gpt, gpt_entry **ptes) +{ + u32 crc, origcrc; + u64 lastlba, pt_size; + + if (!ptes) + return 0; + if (!(*gpt = alloc_read_gpt_header(state, lba))) + return 0; + + /* Check the GUID Partition Table signature */ + if (le64_to_cpu((*gpt)->signature) != GPT_HEADER_SIGNATURE) { + pr_debug("GUID Partition Table Header signature is wrong:" + "%lld != %lld\n", + (unsigned long long)le64_to_cpu((*gpt)->signature), + (unsigned long long)GPT_HEADER_SIGNATURE); + goto fail; + } + + /* Check the GUID Partition Table header size is too big */ + if (le32_to_cpu((*gpt)->header_size) > + queue_logical_block_size(state->disk->queue)) { + pr_debug("GUID Partition Table Header size is too large: %u > %u\n", + le32_to_cpu((*gpt)->header_size), + queue_logical_block_size(state->disk->queue)); + goto fail; + } + + /* Check the GUID Partition Table header size is too small */ + if (le32_to_cpu((*gpt)->header_size) < sizeof(gpt_header)) { + pr_debug("GUID Partition Table Header size is too small: %u < %zu\n", + le32_to_cpu((*gpt)->header_size), + sizeof(gpt_header)); + goto fail; + } + + /* Check the GUID Partition Table CRC */ + origcrc = le32_to_cpu((*gpt)->header_crc32); + (*gpt)->header_crc32 = 0; + crc = efi_crc32((const unsigned char *) (*gpt), le32_to_cpu((*gpt)->header_size)); + + if (crc != origcrc) { + pr_debug("GUID Partition Table Header CRC is wrong: %x != %x\n", + crc, origcrc); + goto fail; + } + (*gpt)->header_crc32 = cpu_to_le32(origcrc); + + /* Check that the my_lba entry points to the LBA that contains + * the GUID Partition Table */ + if (le64_to_cpu((*gpt)->my_lba) != lba) { + pr_debug("GPT my_lba incorrect: %lld != %lld\n", + (unsigned long long)le64_to_cpu((*gpt)->my_lba), + (unsigned long long)lba); + goto fail; + } + + /* Check the first_usable_lba and last_usable_lba are + * within the disk. + */ + lastlba = last_lba(state->disk); + if (le64_to_cpu((*gpt)->first_usable_lba) > lastlba) { + pr_debug("GPT: first_usable_lba incorrect: %lld > %lld\n", + (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba), + (unsigned long long)lastlba); + goto fail; + } + if (le64_to_cpu((*gpt)->last_usable_lba) > lastlba) { + pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n", + (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba), + (unsigned long long)lastlba); + goto fail; + } + if (le64_to_cpu((*gpt)->last_usable_lba) < le64_to_cpu((*gpt)->first_usable_lba)) { + pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n", + (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba), + (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba)); + goto fail; + } + /* Check that sizeof_partition_entry has the correct value */ + if (le32_to_cpu((*gpt)->sizeof_partition_entry) != sizeof(gpt_entry)) { + pr_debug("GUID Partition Entry Size check failed.\n"); + goto fail; + } + + /* Sanity check partition table size */ + pt_size = (u64)le32_to_cpu((*gpt)->num_partition_entries) * + le32_to_cpu((*gpt)->sizeof_partition_entry); + if (pt_size > KMALLOC_MAX_SIZE) { + pr_debug("GUID Partition Table is too large: %llu > %lu bytes\n", + (unsigned long long)pt_size, KMALLOC_MAX_SIZE); + goto fail; + } + + if (!(*ptes = alloc_read_gpt_entries(state, *gpt))) + goto fail; + + /* Check the GUID Partition Entry Array CRC */ + crc = efi_crc32((const unsigned char *) (*ptes), pt_size); + + if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) { + pr_debug("GUID Partition Entry Array CRC check failed.\n"); + goto fail_ptes; + } + + /* We're done, all's well */ + return 1; + + fail_ptes: + kfree(*ptes); + *ptes = NULL; + fail: + kfree(*gpt); + *gpt = NULL; + return 0; +} + +/** + * is_pte_valid() - tests one PTE for validity + * @pte:pte to check + * @lastlba: last lba of the disk + * + * Description: returns 1 if valid, 0 on error. + */ +static inline int +is_pte_valid(const gpt_entry *pte, const u64 lastlba) +{ + if ((!efi_guidcmp(pte->partition_type_guid, NULL_GUID)) || + le64_to_cpu(pte->starting_lba) > lastlba || + le64_to_cpu(pte->ending_lba) > lastlba) + return 0; + return 1; +} + +/** + * compare_gpts() - Search disk for valid GPT headers and PTEs + * @pgpt: primary GPT header + * @agpt: alternate GPT header + * @lastlba: last LBA number + * + * Description: Returns nothing. Sanity checks pgpt and agpt fields + * and prints warnings on discrepancies. + * + */ +static void +compare_gpts(gpt_header *pgpt, gpt_header *agpt, u64 lastlba) +{ + int error_found = 0; + if (!pgpt || !agpt) + return; + if (le64_to_cpu(pgpt->my_lba) != le64_to_cpu(agpt->alternate_lba)) { + pr_warn("GPT:Primary header LBA != Alt. header alternate_lba\n"); + pr_warn("GPT:%lld != %lld\n", + (unsigned long long)le64_to_cpu(pgpt->my_lba), + (unsigned long long)le64_to_cpu(agpt->alternate_lba)); + error_found++; + } + if (le64_to_cpu(pgpt->alternate_lba) != le64_to_cpu(agpt->my_lba)) { + pr_warn("GPT:Primary header alternate_lba != Alt. header my_lba\n"); + pr_warn("GPT:%lld != %lld\n", + (unsigned long long)le64_to_cpu(pgpt->alternate_lba), + (unsigned long long)le64_to_cpu(agpt->my_lba)); + error_found++; + } + if (le64_to_cpu(pgpt->first_usable_lba) != + le64_to_cpu(agpt->first_usable_lba)) { + pr_warn("GPT:first_usable_lbas don't match.\n"); + pr_warn("GPT:%lld != %lld\n", + (unsigned long long)le64_to_cpu(pgpt->first_usable_lba), + (unsigned long long)le64_to_cpu(agpt->first_usable_lba)); + error_found++; + } + if (le64_to_cpu(pgpt->last_usable_lba) != + le64_to_cpu(agpt->last_usable_lba)) { + pr_warn("GPT:last_usable_lbas don't match.\n"); + pr_warn("GPT:%lld != %lld\n", + (unsigned long long)le64_to_cpu(pgpt->last_usable_lba), + (unsigned long long)le64_to_cpu(agpt->last_usable_lba)); + error_found++; + } + if (efi_guidcmp(pgpt->disk_guid, agpt->disk_guid)) { + pr_warn("GPT:disk_guids don't match.\n"); + error_found++; + } + if (le32_to_cpu(pgpt->num_partition_entries) != + le32_to_cpu(agpt->num_partition_entries)) { + pr_warn("GPT:num_partition_entries don't match: " + "0x%x != 0x%x\n", + le32_to_cpu(pgpt->num_partition_entries), + le32_to_cpu(agpt->num_partition_entries)); + error_found++; + } + if (le32_to_cpu(pgpt->sizeof_partition_entry) != + le32_to_cpu(agpt->sizeof_partition_entry)) { + pr_warn("GPT:sizeof_partition_entry values don't match: " + "0x%x != 0x%x\n", + le32_to_cpu(pgpt->sizeof_partition_entry), + le32_to_cpu(agpt->sizeof_partition_entry)); + error_found++; + } + if (le32_to_cpu(pgpt->partition_entry_array_crc32) != + le32_to_cpu(agpt->partition_entry_array_crc32)) { + pr_warn("GPT:partition_entry_array_crc32 values don't match: " + "0x%x != 0x%x\n", + le32_to_cpu(pgpt->partition_entry_array_crc32), + le32_to_cpu(agpt->partition_entry_array_crc32)); + error_found++; + } + if (le64_to_cpu(pgpt->alternate_lba) != lastlba) { + pr_warn("GPT:Primary header thinks Alt. header is not at the end of the disk.\n"); + pr_warn("GPT:%lld != %lld\n", + (unsigned long long)le64_to_cpu(pgpt->alternate_lba), + (unsigned long long)lastlba); + error_found++; + } + + if (le64_to_cpu(agpt->my_lba) != lastlba) { + pr_warn("GPT:Alternate GPT header not at the end of the disk.\n"); + pr_warn("GPT:%lld != %lld\n", + (unsigned long long)le64_to_cpu(agpt->my_lba), + (unsigned long long)lastlba); + error_found++; + } + + if (error_found) + pr_warn("GPT: Use GNU Parted to correct GPT errors.\n"); + return; +} + +/** + * find_valid_gpt() - Search disk for valid GPT headers and PTEs + * @state: disk parsed partitions + * @gpt: GPT header ptr, filled on return. + * @ptes: PTEs ptr, filled on return. + * + * Description: Returns 1 if valid, 0 on error. + * If valid, returns pointers to newly allocated GPT header and PTEs. + * Validity depends on PMBR being valid (or being overridden by the + * 'gpt' kernel command line option) and finding either the Primary + * GPT header and PTEs valid, or the Alternate GPT header and PTEs + * valid. If the Primary GPT header is not valid, the Alternate GPT header + * is not checked unless the 'gpt' kernel command line option is passed. + * This protects against devices which misreport their size, and forces + * the user to decide to use the Alternate GPT. + */ +static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt, + gpt_entry **ptes) +{ + int good_pgpt = 0, good_agpt = 0, good_pmbr = 0; + gpt_header *pgpt = NULL, *agpt = NULL; + gpt_entry *pptes = NULL, *aptes = NULL; + legacy_mbr *legacymbr; + struct gendisk *disk = state->disk; + const struct block_device_operations *fops = disk->fops; + sector_t total_sectors = get_capacity(state->disk); + u64 lastlba; + + if (!ptes) + return 0; + + lastlba = last_lba(state->disk); + if (!force_gpt) { + /* This will be added to the EFI Spec. per Intel after v1.02. */ + legacymbr = kzalloc(sizeof(*legacymbr), GFP_KERNEL); + if (!legacymbr) + goto fail; + + read_lba(state, 0, (u8 *)legacymbr, sizeof(*legacymbr)); + good_pmbr = is_pmbr_valid(legacymbr, total_sectors); + kfree(legacymbr); + + if (!good_pmbr) + goto fail; + + pr_debug("Device has a %s MBR\n", + good_pmbr == GPT_MBR_PROTECTIVE ? + "protective" : "hybrid"); + } + + good_pgpt = is_gpt_valid(state, GPT_PRIMARY_PARTITION_TABLE_LBA, + &pgpt, &pptes); + if (good_pgpt) + good_agpt = is_gpt_valid(state, + le64_to_cpu(pgpt->alternate_lba), + &agpt, &aptes); + if (!good_agpt && force_gpt) + good_agpt = is_gpt_valid(state, lastlba, &agpt, &aptes); + + if (!good_agpt && force_gpt && fops->alternative_gpt_sector) { + sector_t agpt_sector; + int err; + + err = fops->alternative_gpt_sector(disk, &agpt_sector); + if (!err) + good_agpt = is_gpt_valid(state, agpt_sector, + &agpt, &aptes); + } + + /* The obviously unsuccessful case */ + if (!good_pgpt && !good_agpt) + goto fail; + + compare_gpts(pgpt, agpt, lastlba); + + /* The good cases */ + if (good_pgpt) { + *gpt = pgpt; + *ptes = pptes; + kfree(agpt); + kfree(aptes); + if (!good_agpt) + pr_warn("Alternate GPT is invalid, using primary GPT.\n"); + return 1; + } + else if (good_agpt) { + *gpt = agpt; + *ptes = aptes; + kfree(pgpt); + kfree(pptes); + pr_warn("Primary GPT is invalid, using alternate GPT.\n"); + return 1; + } + + fail: + kfree(pgpt); + kfree(agpt); + kfree(pptes); + kfree(aptes); + *gpt = NULL; + *ptes = NULL; + return 0; +} + +/** + * utf16_le_to_7bit(): Naively converts a UTF-16LE string to 7-bit ASCII characters + * @in: input UTF-16LE string + * @size: size of the input string + * @out: output string ptr, should be capable to store @size+1 characters + * + * Description: Converts @size UTF16-LE symbols from @in string to 7-bit + * ASCII characters and stores them to @out. Adds trailing zero to @out array. + */ +static void utf16_le_to_7bit(const __le16 *in, unsigned int size, u8 *out) +{ + unsigned int i = 0; + + out[size] = 0; + + while (i < size) { + u8 c = le16_to_cpu(in[i]) & 0xff; + + if (c && !isprint(c)) + c = '!'; + out[i] = c; + i++; + } +} + +/** + * efi_partition - scan for GPT partitions + * @state: disk parsed partitions + * + * Description: called from check.c, if the disk contains GPT + * partitions, sets up partition entries in the kernel. + * + * If the first block on the disk is a legacy MBR, + * it will get handled by msdos_partition(). + * If it's a Protective MBR, we'll handle it here. + * + * We do not create a Linux partition for GPT, but + * only for the actual data partitions. + * Returns: + * -1 if unable to read the partition table + * 0 if this isn't our partition table + * 1 if successful + * + */ +int efi_partition(struct parsed_partitions *state) +{ + gpt_header *gpt = NULL; + gpt_entry *ptes = NULL; + u32 i; + unsigned ssz = queue_logical_block_size(state->disk->queue) / 512; + + if (!find_valid_gpt(state, &gpt, &ptes) || !gpt || !ptes) { + kfree(gpt); + kfree(ptes); + return 0; + } + + pr_debug("GUID Partition Table is valid! Yea!\n"); + + for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) { + struct partition_meta_info *info; + unsigned label_max; + u64 start = le64_to_cpu(ptes[i].starting_lba); + u64 size = le64_to_cpu(ptes[i].ending_lba) - + le64_to_cpu(ptes[i].starting_lba) + 1ULL; + + if (!is_pte_valid(&ptes[i], last_lba(state->disk))) + continue; + + put_partition(state, i+1, start * ssz, size * ssz); + + /* If this is a RAID volume, tell md */ + if (!efi_guidcmp(ptes[i].partition_type_guid, PARTITION_LINUX_RAID_GUID)) + state->parts[i + 1].flags = ADDPART_FLAG_RAID; + + info = &state->parts[i + 1].info; + efi_guid_to_str(&ptes[i].unique_partition_guid, info->uuid); + + /* Naively convert UTF16-LE to 7 bits. */ + label_max = min(ARRAY_SIZE(info->volname) - 1, + ARRAY_SIZE(ptes[i].partition_name)); + utf16_le_to_7bit(ptes[i].partition_name, label_max, info->volname); + state->parts[i + 1].has_info = true; + } + kfree(ptes); + kfree(gpt); + strlcat(state->pp_buf, "\n", PAGE_SIZE); + return 1; +} -- cgit v1.2.3