grub/disk/mdraid_linux.c
Peter Henn 3b97788878 * disk/mdraid_linux.c (grub_mdraid_detect): Fix calculation of 1.x
chunk size and disk size, which are already given as sector counts
as distinct from the 0.90 units.  Fetch the correct device number
from the role table instead of using the table index.
2010-06-01 18:40:03 +01:00

408 lines
13 KiB
C

/* mdraid_linux.c - module to handle Linux Software RAID. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2008,2009 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));
/*
* The version-1 superblock :
* All numeric fields are little-endian.
*
* Total size: 256 bytes plus 2 per device.
* 1K allows 384 devices.
*/
struct grub_raid_super_1x
{
/* Constant array information - 128 bytes. */
grub_uint32_t magic; /* MD_SB_MAGIC: 0xa92b4efc - little endian. */
grub_uint32_t major_version; /* 1. */
grub_uint32_t feature_map; /* Bit 0 set if 'bitmap_offset' is meaningful. */
grub_uint32_t pad0; /* Always set to 0 when writing. */
grub_uint8_t set_uuid[16]; /* User-space generated. */
char set_name[32]; /* Set and interpreted by user-space. */
grub_uint64_t ctime; /* Lo 40 bits are seconds, top 24 are microseconds or 0. */
grub_uint32_t level; /* -4 (multipath), -1 (linear), 0,1,4,5. */
grub_uint32_t layout; /* only for raid5 and raid10 currently. */
grub_uint64_t size; /* Used size of component devices, in 512byte sectors. */
grub_uint32_t chunksize; /* In 512byte sectors. */
grub_uint32_t raid_disks;
grub_uint32_t bitmap_offset; /* Sectors after start of superblock that bitmap starts
* NOTE: signed, so bitmap can be before superblock
* only meaningful of feature_map[0] is set.
*/
/* These are only valid with feature bit '4'. */
grub_uint32_t new_level; /* New level we are reshaping to. */
grub_uint64_t reshape_position; /* Next address in array-space for reshape. */
grub_uint32_t delta_disks; /* Change in number of raid_disks. */
grub_uint32_t new_layout; /* New layout. */
grub_uint32_t new_chunk; /* New chunk size (512byte sectors). */
grub_uint8_t pad1[128 - 124]; /* Set to 0 when written. */
/* Constant this-device information - 64 bytes. */
grub_uint64_t data_offset; /* Sector start of data, often 0. */
grub_uint64_t data_size; /* Sectors in this device that can be used for data. */
grub_uint64_t super_offset; /* Sector start of this superblock. */
grub_uint64_t recovery_offset; /* Sectors before this offset (from data_offset) have been recovered. */
grub_uint32_t dev_number; /* Permanent identifier of this device - not role in raid. */
grub_uint32_t cnt_corrected_read; /* Number of read errors that were corrected by re-writing. */
grub_uint8_t device_uuid[16]; /* User-space setable, ignored by kernel. */
grub_uint8_t devflags; /* Per-device flags. Only one defined... */
grub_uint8_t pad2[64 - 57]; /* Set to 0 when writing. */
/* Array state information - 64 bytes. */
grub_uint64_t utime; /* 40 bits second, 24 btes microseconds. */
grub_uint64_t events; /* Incremented when superblock updated. */
grub_uint64_t resync_offset; /* Data before this offset (from data_offset) known to be in sync. */
grub_uint32_t sb_csum; /* Checksum upto devs[max_dev]. */
grub_uint32_t max_dev; /* Size of devs[] array to consider. */
grub_uint8_t pad3[64 - 32]; /* Set to 0 when writing. */
/* Device state information. Indexed by dev_number.
* 2 bytes per device.
* Note there are no per-device state flags. State information is rolled
* into the 'roles' value. If a device is spare or faulty, then it doesn't
* have a meaningful role.
*/
grub_uint16_t dev_roles[0]; /* Role in array, or 0xffff for a spare, or 0xfffe for faulty. */
} __attribute__ ((packed));
#define WriteMostly1 1 /* Mask for writemostly flag in above devflags. */
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, sb_size;
struct grub_raid_super_09 sb;
struct grub_raid_super_1x *sb_1x;
grub_uint32_t *uuid;
grub_uint8_t minor_version;
/* The sector where the mdraid 0.90 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 mdraid 0.90 superblock. */
if (sb.md_magic == SB_MAGIC)
goto superblock_0_90;
/* Check for an 1.x superblock.
* It's always aligned to a 4K boundary
* and depending on the minor version it can be:
* 0: At least 8K, but less than 12K, from end of device
* 1: At start of device
* 2: 4K from start of device.
*/
sb_1x = grub_malloc (sizeof (struct grub_raid_super_1x));
if (!sb_1x)
return grub_errno;
for (minor_version = 0; minor_version < 3; ++minor_version)
{
switch (minor_version)
{
case 0:
sector = (size - 8 * 2) & ~(4 * 2 - 1);
break;
case 1:
sector = 0;
break;
case 2:
sector = 4 * 2;
break;
}
if (grub_disk_read
(disk, sector, 0, sizeof (struct grub_raid_super_1x), sb_1x))
{
grub_free (sb_1x);
return grub_errno;
}
if (sb_1x->magic == SB_MAGIC)
goto superblock_1_x;
}
/* Neither 0.90 nor 1.x. */
if (grub_le_to_cpu32 (sb_1x->magic) != SB_MAGIC)
return grub_error (GRUB_ERR_OUT_OF_RANGE, "not raid");
superblock_0_90:
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->name = NULL;
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;
superblock_1_x:
if (sb_1x->major_version != 1)
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
"Unsupported RAID version: %d",
sb_1x->major_version);
/* Multipath. */
if ((int) sb_1x->level == -4)
sb_1x->level = 1;
if (sb_1x->level != 0 && sb_1x->level != 1 && sb_1x->level != 4 &&
sb_1x->level != 5 && sb_1x->level != 6 && sb_1x->level != 10)
{
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
"Unsupported RAID level: %d", sb_1x->level);
grub_free (sb_1x);
}
/* 1.x superblocks don't have a fixed size on disk. So we have to
read it again now that we now the max device count. */
sb_size = sizeof (struct grub_raid_super_1x) + 2 * grub_le_to_cpu32 (sb_1x->max_dev);
sb_1x = grub_realloc (sb_1x, sb_size);
if (! sb_1x)
return grub_errno;
if (grub_disk_read (disk, sector, 0, sb_size, sb_1x))
{
grub_free (sb_1x);
return grub_errno;
}
array->name = grub_strdup (sb_1x->set_name);
if (! array->name)
{
grub_free (sb_1x);
return grub_errno;
}
array->number = 0;
array->level = grub_le_to_cpu32 (sb_1x->level);
array->layout = grub_le_to_cpu32 (sb_1x->layout);
array->total_devs = grub_le_to_cpu32 (sb_1x->raid_disks);
array->disk_size = grub_le_to_cpu64 (sb_1x->size);
array->chunk_size = grub_le_to_cpu32 (sb_1x->chunksize);
if (grub_le_to_cpu32 (sb_1x->dev_number) < grub_le_to_cpu32 (sb_1x->max_dev))
array->index = grub_le_to_cpu16 (sb_1x->dev_roles[grub_le_to_cpu32 (sb_1x->dev_number)]);
else
array->index = 0xffff; /* disk will be later not used! */
array->uuid_len = 16;
array->uuid = grub_malloc (16);
if (!array->uuid)
{
grub_free (sb_1x);
return grub_errno;
}
grub_memcpy (array->uuid, sb_1x->set_uuid, 16);
grub_free (sb_1x);
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);
}