/* mdraid_linux.c - module to handle linux softraid. */ /* * GRUB -- GRand Unified Bootloader * Copyright (C) 2008 Free Software Foundation, Inc. * * GRUB is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * GRUB is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with GRUB. If not, see <http://www.gnu.org/licenses/>. */ #include <grub/dl.h> #include <grub/disk.h> #include <grub/mm.h> #include <grub/err.h> #include <grub/misc.h> #include <grub/raid.h> /* Linux RAID on disk structures and constants, copied from include/linux/raid/md_p.h. */ #define RESERVED_BYTES (64 * 1024) #define RESERVED_SECTORS (RESERVED_BYTES / 512) #define NEW_SIZE_SECTORS(x) ((x & ~(RESERVED_SECTORS - 1)) \ - RESERVED_SECTORS) #define SB_BYTES 4096 #define SB_WORDS (SB_BYTES / 4) #define SB_SECTORS (SB_BYTES / 512) /* * The following are counted in 32-bit words */ #define SB_GENERIC_OFFSET 0 #define SB_PERSONALITY_OFFSET 64 #define SB_DISKS_OFFSET 128 #define SB_DESCRIPTOR_OFFSET 992 #define SB_GENERIC_CONSTANT_WORDS 32 #define SB_GENERIC_STATE_WORDS 32 #define SB_GENERIC_WORDS (SB_GENERIC_CONSTANT_WORDS + \ SB_GENERIC_STATE_WORDS) #define SB_PERSONALITY_WORDS 64 #define SB_DESCRIPTOR_WORDS 32 #define SB_DISKS 27 #define SB_DISKS_WORDS (SB_DISKS * SB_DESCRIPTOR_WORDS) #define SB_RESERVED_WORDS (1024 \ - SB_GENERIC_WORDS \ - SB_PERSONALITY_WORDS \ - SB_DISKS_WORDS \ - SB_DESCRIPTOR_WORDS) #define SB_EQUAL_WORDS (SB_GENERIC_WORDS \ + SB_PERSONALITY_WORDS \ + SB_DISKS_WORDS) /* * Device "operational" state bits */ #define DISK_FAULTY 0 #define DISK_ACTIVE 1 #define DISK_SYNC 2 #define DISK_REMOVED 3 #define DISK_WRITEMOSTLY 9 #define SB_MAGIC 0xa92b4efc /* * Superblock state bits */ #define SB_CLEAN 0 #define SB_ERRORS 1 #define SB_BITMAP_PRESENT 8 struct grub_raid_disk_09 { grub_uint32_t number; /* Device number in the entire set. */ grub_uint32_t major; /* Device major number. */ grub_uint32_t minor; /* Device minor number. */ grub_uint32_t raid_disk; /* The role of the device in the raid set. */ grub_uint32_t state; /* Operational state. */ grub_uint32_t reserved[SB_DESCRIPTOR_WORDS - 5]; }; struct grub_raid_super_09 { /* * Constant generic information */ grub_uint32_t md_magic; /* MD identifier. */ grub_uint32_t major_version; /* Major version. */ grub_uint32_t minor_version; /* Minor version. */ grub_uint32_t patch_version; /* Patchlevel version. */ grub_uint32_t gvalid_words; /* Number of used words in this section. */ grub_uint32_t set_uuid0; /* Raid set identifier. */ grub_uint32_t ctime; /* Creation time. */ grub_uint32_t level; /* Raid personality. */ grub_uint32_t size; /* Apparent size of each individual disk. */ grub_uint32_t nr_disks; /* Total disks in the raid set. */ grub_uint32_t raid_disks; /* Disks in a fully functional raid set. */ grub_uint32_t md_minor; /* Preferred MD minor device number. */ grub_uint32_t not_persistent; /* Does it have a persistent superblock. */ grub_uint32_t set_uuid1; /* Raid set identifier #2. */ grub_uint32_t set_uuid2; /* Raid set identifier #3. */ grub_uint32_t set_uuid3; /* Raid set identifier #4. */ grub_uint32_t gstate_creserved[SB_GENERIC_CONSTANT_WORDS - 16]; /* * Generic state information */ grub_uint32_t utime; /* Superblock update time. */ grub_uint32_t state; /* State bits (clean, ...). */ grub_uint32_t active_disks; /* Number of currently active disks. */ grub_uint32_t working_disks; /* Number of working disks. */ grub_uint32_t failed_disks; /* Number of failed disks. */ grub_uint32_t spare_disks; /* Number of spare disks. */ grub_uint32_t sb_csum; /* Checksum of the whole superblock. */ grub_uint64_t events; /* Superblock update count. */ grub_uint64_t cp_events; /* Checkpoint update count. */ grub_uint32_t recovery_cp; /* Recovery checkpoint sector count. */ grub_uint32_t gstate_sreserved[SB_GENERIC_STATE_WORDS - 12]; /* * Personality information */ grub_uint32_t layout; /* The array's physical layout. */ grub_uint32_t chunk_size; /* Chunk size in bytes. */ grub_uint32_t root_pv; /* LV root PV. */ grub_uint32_t root_block; /* LV root block. */ grub_uint32_t pstate_reserved[SB_PERSONALITY_WORDS - 4]; /* * Disks information */ struct grub_raid_disk_09 disks[SB_DISKS]; /* * Reserved */ grub_uint32_t reserved[SB_RESERVED_WORDS]; /* * Active descriptor */ struct grub_raid_disk_09 this_disk; } __attribute__ ((packed)); static grub_err_t grub_mdraid_detect (grub_disk_t disk, struct grub_raid_array *array) { grub_disk_addr_t sector; grub_uint64_t size; struct grub_raid_super_09 sb; grub_uint32_t *uuid; /* The sector where the RAID superblock is stored, if available. */ size = grub_disk_get_size (disk); sector = NEW_SIZE_SECTORS (size); if (grub_disk_read (disk, sector, 0, SB_BYTES, &sb)) return grub_errno; /* Look whether there is a RAID superblock. */ if (sb.md_magic != SB_MAGIC) return grub_error (GRUB_ERR_OUT_OF_RANGE, "not raid"); /* FIXME: Also support version 1.0. */ if (sb.major_version != 0 || sb.minor_version != 90) return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, "unsupported RAID version: %d.%d", sb.major_version, sb.minor_version); /* FIXME: Check the checksum. */ /* Multipath. */ if ((int) sb.level == -4) sb.level = 1; if (sb.level != 0 && sb.level != 1 && sb.level != 4 && sb.level != 5 && sb.level != 6 && sb.level != 10) return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, "unsupported RAID level: %d", sb.level); array->number = sb.md_minor; array->level = sb.level; array->layout = sb.layout; array->total_devs = sb.raid_disks; array->disk_size = (sb.size) ? sb.size * 2 : sector; array->chunk_size = sb.chunk_size >> 9; array->index = sb.this_disk.number; array->uuid_len = 16; array->uuid = grub_malloc (16); if (!array->uuid) return grub_errno; uuid = (grub_uint32_t *) array->uuid; uuid[0] = sb.set_uuid0; uuid[1] = sb.set_uuid1; uuid[2] = sb.set_uuid2; uuid[3] = sb.set_uuid3; return 0; } static struct grub_raid grub_mdraid_dev = { .name = "mdraid", .detect = grub_mdraid_detect, .next = 0 }; GRUB_MOD_INIT (mdraid) { grub_raid_register (&grub_mdraid_dev); } GRUB_MOD_FINI (mdraid) { grub_raid_unregister (&grub_mdraid_dev); }