freebsd-dev/sys/dev/ata/ata-raid.h
Søren Schmidt 8ca4df3299 This is the much rumoured ATA mkIII update that I've been working on.
o       ATA is now fully newbus'd and split into modules.
        This means that on a modern system you just load "atapci and ata"
        to get the base support, and then one or more of the device
        subdrivers "atadisk atapicd atapifd atapist ataraid".
        All can be loaded/unloaded anytime, but for obvious reasons you
        dont want to unload atadisk when you have mounted filesystems.

o       The device identify part of the probe has been rewritten to fix
        the problems with odd devices the old had, and to try to remove
        so of the long delays some HW could provoke. Also probing is done
	without the need for interrupts, making earlier probing possible.

o       SATA devices can be hot inserted/removed and devices will be created/
        removed in /dev accordingly.
	NOTE: only supported on controllers that has this feature:
	Promise and Silicon Image for now.
	On other controllers the usual atacontrol detach/attach dance is
	still needed.

o	Support for "atomic" composite ATA requests used for RAID.

o       ATA RAID support has been rewritten and and now supports these
        metadata formats:
                 "Adaptec HostRAID"
                 "Highpoint V2 RocketRAID"
                 "Highpoint V3 RocketRAID"
                 "Intel MatrixRAID"
                 "Integrated Technology Express"
                 "LSILogic V2 MegaRAID"
                 "LSILogic V3 MegaRAID"
                 "Promise FastTrak"
                 "Silicon Image Medley"
		 "FreeBSD PseudoRAID"

o       Update the ioctl API to match new RAID levels etc.

o       Update atacontrol to know about the new RAID levels etc
        NOTE: you need to recompile atacontrol with the new sys/ata.h,
        make world will take care of that.
	NOTE2: that rebuild is done differently from the old system as
	the rebuild is now done piggybacked on read requests to the
	array, so atacontrol simply starts a background "dd" to rebuild
	the array.

o       The reinit code has been worked over to be much more robust.

o       The timeout code has been overhauled for races.

o	Support of new chipsets.

o       Lots of fixes for bugs found while doing the modulerization and
        reviewing the old code.

Missing or changed features from current ATA:

o       atapi-cd no longer has support for ATAPI changers. Todays its
        much cheaper and alot faster to copy those CD images to disk
        and serve them from there. Besides they dont seem to be made
        anymore, maybe for that exact reason.

o       ATA RAID can only read metadata from all the above metadata formats,
	not write all of them (Promise and Highpoint V2 so far). This means
	that arrays can be picked up from the BIOS, but they cannot be
	created from FreeBSD. There is more to it than just the missing
	write metadata support, those formats are not unique to a given
	controller like Promise and Highpoint formats, instead they exist
	for several types, and even worse, some controllers can have
	different formats and its impossible to tell which one.
	The outcome is that we cannot reliably create the metadata of those
	formats and be sure the controller BIOS will understand it.
	However write support is needed to update/fail/rebuild the arrays
	properly so it sits fairly high on the TODO list.

o       So far atapicam is not supported with these changes. When/if this
	will change is up to the maintainer of atapi-cam so go there for
	questions.

HW donated by:  Webveveriet AS
HW donated by:  Frode Nordahl
HW donated by:  Yahoo!
HW donated by:  Sentex
Patience by:	Vife and my boys (and even the cats)
2005-03-30 12:03:40 +00:00

643 lines
20 KiB
C

/*-
* Copyright (c) 2000 - 2005 Søren Schmidt <sos@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer,
* without modification, immediately at the beginning of the file.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
/* misc defines */
#define MAX_ARRAYS 16
#define MAX_DISKS 16
#define AR_PROXIMITY 2048 /* how many sectors is "close" */
#define ATA_MAGIC "FreeBSD ATA driver RAID "
struct ata_raid_subdisk {
struct ar_softc *raid;
int disk_number;
};
/* ATA PseudoRAID Metadata */
struct ar_softc {
int lun; /* logical unit number of this RAID */
u_int8_t name[32]; /* name of array if any */
u_int64_t magic_0; /* magic for this array */
u_int64_t magic_1; /* magic for this array */
int type;
#define AR_T_JBOD 0x0001
#define AR_T_SPAN 0x0002
#define AR_T_RAID0 0x0004
#define AR_T_RAID1 0x0008
#define AR_T_RAID01 0x0010
#define AR_T_RAID3 0x0020
#define AR_T_RAID4 0x0040
#define AR_T_RAID5 0x0080
int status;
#define AR_S_READY 0x0001
#define AR_S_DEGRADED 0x0002
#define AR_S_REBUILDING 0x0004
int format;
#define AR_F_FREEBSD_RAID 0x0001
#define AR_F_ADAPTEC_RAID 0x0002
#define AR_F_HPTV2_RAID 0x0004
#define AR_F_HPTV3_RAID 0x0008
#define AR_F_INTEL_RAID 0x0010
#define AR_F_ITE_RAID 0x0020
#define AR_F_LSIV2_RAID 0x0040
#define AR_F_LSIV3_RAID 0x0080
#define AR_F_PROMISE_RAID 0x0100
#define AR_F_SII_RAID 0x0200
#define AR_F_FORMAT_MASK 0x03ff
u_int generation; /* generation of this array */
u_int64_t total_sectors;
u_int64_t offset_sectors; /* offset from start of disk */
u_int16_t heads;
u_int16_t sectors;
u_int32_t cylinders;
u_int width; /* array width in disks */
u_int interleave; /* interleave in blocks */
u_int total_disks; /* number of disks in this array */
struct ar_disk {
device_t dev;
u_int8_t serial[16]; /* serial # of physical disk */
u_int64_t sectors; /* useable sectors on this disk */
off_t last_lba; /* last lba used (for performance) */
u_int flags;
#define AR_DF_PRESENT 0x0001 /* this HW pos has a disk present */
#define AR_DF_ASSIGNED 0x0002 /* this HW pos assigned to an array */
#define AR_DF_SPARE 0x0004 /* this HW pos is a spare */
#define AR_DF_ONLINE 0x0008 /* this HW pos is online and in use */
} disks[MAX_DISKS];
int toggle; /* performance hack for RAID1's */
u_int64_t rebuild_lba; /* rebuild progress indicator */
struct mtx lock; /* metadata lock */
struct disk *disk; /* disklabel/slice stuff */
struct proc *pid; /* rebuilder process id */
};
/* Adaptec HostRAID Metadata */
#define ADP_LBA(dev) \
(((struct ad_softc *)device_get_ivars(dev))->total_secs - 17)
/* note all entries are big endian */
struct adaptec_raid_conf {
u_int32_t magic_0; /* 0x0000 */
#define ADP_MAGIC_0 0xc4650790
u_int32_t generation;
u_int16_t dummy_0;
u_int16_t total_configs;
u_int16_t dummy_1;
u_int16_t checksum;
u_int32_t dummy_2; /* 0x0010 */
u_int32_t dummy_3;
u_int32_t flags;
u_int32_t timestamp;
u_int32_t dummy_4[4]; /* 0x0020 */
u_int32_t dummy_5[4]; /* 0x0030 */
struct { /* 0x0040 */
u_int16_t total_disks;
u_int16_t generation;
u_int32_t magic_0;
u_int8_t dummy_0;
u_int8_t type;
#define ADP_T_RAID0 0x00
#define ADP_T_RAID1 0x01
u_int8_t dummy_1;
u_int8_t flags;
u_int8_t dummy_2;
u_int8_t dummy_3;
u_int8_t dummy_4;
u_int8_t dummy_5;
u_int32_t disk_number;
u_int32_t dummy_6;
u_int32_t sectors;
u_int16_t stripe_shift;
u_int16_t dummy_7;
u_int32_t dummy_8[4];
u_int8_t name[16];
} configs[127]; /* x 0x40 bytes */
u_int32_t dummy_6[13]; /* 0x2000 */
u_int32_t magic_1;
#define ADP_MAGIC_1 0x9ff85009
u_int32_t dummy_7[3];
u_int32_t magic_2;
u_int32_t dummy_8[46];
u_int32_t magic_3;
#define ADP_MAGIC_3 0x4d545044
u_int32_t magic_4;
#define ADP_MAGIC_4 0x9ff85009
u_int32_t dummy_9[62];
} __packed;
/* Highpoint V2 RocketRAID Metadata */
#define HPTV2_LBA(dev) 9
struct hptv2_raid_conf {
int8_t filler1[32];
u_int32_t magic;
#define HPTV2_MAGIC_OK 0x5a7816f0
#define HPTV2_MAGIC_BAD 0x5a7816fd
u_int32_t magic_0;
u_int32_t magic_1;
u_int32_t order;
#define HPTV2_O_RAID0 0x01
#define HPTV2_O_RAID1 0x02
#define HPTV2_O_OK 0x04
u_int8_t array_width;
u_int8_t stripe_shift;
u_int8_t type;
#define HPTV2_T_RAID0 0x00
#define HPTV2_T_RAID1 0x01
#define HPTV2_T_RAID01_RAID0 0x02
#define HPTV2_T_SPAN 0x03
#define HPTV2_T_RAID_3 0x04
#define HPTV2_T_RAID_5 0x05
#define HPTV2_T_JBOD 0x06
#define HPTV2_T_RAID01_RAID1 0x07
u_int8_t disk_number;
u_int32_t total_sectors;
u_int32_t disk_mode;
u_int32_t boot_mode;
u_int8_t boot_disk;
u_int8_t boot_protect;
u_int8_t error_log_entries;
u_int8_t error_log_index;
struct {
u_int32_t timestamp;
u_int8_t reason;
#define HPTV2_R_REMOVED 0xfe
#define HPTV2_R_BROKEN 0xff
u_int8_t disk;
u_int8_t status;
u_int8_t sectors;
u_int32_t lba;
} errorlog[32];
int8_t filler2[16];
u_int32_t rebuild_lba;
u_int8_t dummy_1;
u_int8_t name_1[15];
u_int8_t dummy_2;
u_int8_t name_2[15];
int8_t filler3[8];
} __packed;
/* Highpoint V3 RocketRAID Metadata */
#define HPTV3_LBA(dev) \
(((struct ad_softc *)device_get_ivars(dev))->total_secs - 11)
struct hptv3_raid_conf {
u_int32_t magic;
#define HPTV3_MAGIC 0x5a7816f3
u_int32_t magic_0;
u_int8_t checksum_0;
u_int8_t mode;
#define HPTV3_BOOT_MARK 0x01
#define HPTV3_USER_MODE 0x02
u_int8_t user_mode;
u_int8_t config_entries;
struct {
u_int32_t total_sectors;
u_int8_t type;
#define HPTV3_T_SPARE 0x00
#define HPTV3_T_JBOD 0x03
#define HPTV3_T_SPAN 0x04
#define HPTV3_T_RAID0 0x05
#define HPTV3_T_RAID1 0x06
#define HPTV3_T_RAID3 0x07
#define HPTV3_T_RAID5 0x08
u_int8_t total_disks;
u_int8_t disk_number;
u_int8_t stripe_shift;
u_int16_t status;
#define HPTV3_T_NEED_REBUILD 0x01
#define HPTV3_T_RAID5_FLAG 0x02
u_int16_t critical_disks;
u_int32_t rebuild_lba;
} __packed configs[2];
u_int8_t name[16];
u_int32_t timestamp;
u_int8_t description[64];
u_int8_t creator[16];
u_int8_t checksum_1;
u_int8_t dummy_0;
u_int8_t dummy_1;
u_int8_t flags;
#define HPTV3_T_ENABLE_TCQ 0x01
#define HPTV3_T_ENABLE_NCQ 0x02
#define HPTV3_T_ENABLE_WCACHE 0x04
#define HPTV3_T_ENABLE_RCACHE 0x08
struct {
u_int32_t total_sectors;
u_int32_t rebuild_lba;
} __packed configs_high[2];
u_int32_t filler[87];
} __packed;
/* Intel MatrixRAID Metadata */
#define INTEL_LBA(dev) \
(((struct ad_softc *)device_get_ivars(dev))->total_secs - 2)
struct intel_raid_conf {
u_int8_t intel_id[24];
#define INTEL_MAGIC "Intel Raid ISM Cfg Sig. "
u_int8_t version[6];
u_int8_t dummy_0[2];
u_int32_t checksum;
u_int32_t config_size;
u_int32_t config_id;
u_int32_t generation;
u_int32_t dummy_1[2];
u_int8_t total_disks;
u_int8_t total_volumes;
u_int8_t dummy_2[2];
u_int32_t filler_0[39];
struct {
u_int8_t serial[16];
u_int32_t sectors;
u_int32_t id;
u_int32_t flags;
#define INTEL_F_SPARE 0x01
#define INTEL_F_ASSIGNED 0x02
#define INTEL_F_DOWN 0x04
#define INTEL_F_ONLINE 0x08
u_int32_t filler[5];
} __packed disk[1];
u_int32_t filler_1[62];
} __packed;
struct intel_raid_mapping {
u_int8_t name[16];
u_int64_t total_sectors __packed;
u_int32_t state;
u_int32_t reserved;
u_int32_t filler_1[20];
u_int32_t offset;
u_int32_t disk_sectors;
u_int32_t stripe_count;
u_int16_t stripe_sectors;
u_int8_t status;
#define INTEL_S_READY 0x00
#define INTEL_S_DISABLED 0x01
#define INTEL_S_DEGRADED 0x02
#define INTEL_S_FAILURE 0x03
u_int8_t type;
#define INTEL_T_RAID0 0x00
#define INTEL_T_RAID1 0x01
u_int8_t total_disks;
u_int8_t dummy_2[3];
u_int32_t filler_2[7];
u_int32_t disk_idx[1];
} __packed;
/* Integrated Technology Express Metadata */
#define ITE_LBA(dev) \
(((struct ad_softc *)device_get_ivars(dev))->total_secs - 2)
struct ite_raid_conf {
u_int32_t filler_1[5];
u_int8_t timestamp_0[8]; /* BCD coded y:Y:M:D:m:h:f:s */
u_int32_t dummy_1;
u_int32_t filler_2[5];
u_int16_t filler_3;
u_int8_t ite_id[40]; /* byte swapped */
#define ITE_MAGIC "Integrated Technology Express Inc "
u_int16_t filler_4;
u_int32_t filler_5[6];
u_int32_t dummy_2;
u_int32_t dummy_3;
u_int32_t filler_6[12];
u_int32_t dummy_4;
u_int32_t filler_7[5];
u_int64_t total_sectors __packed;
u_int32_t filler_8[12];
u_int16_t filler_9; /* 0x100 */
u_int8_t type;
#define ITE_T_RAID0 0x00
#define ITE_T_RAID1 0x01
#define ITE_T_RAID01 0x02
#define ITE_T_SPAN 0x03
u_int8_t filler_10;
u_int32_t dummy_5[8];
u_int8_t stripe_1kblocks;
u_int8_t filler_11[3];
u_int32_t filler_12[54];
u_int32_t dummy_6[4]; /* 0x200 */
u_int8_t timestamp_1[8]; /* same as timestamp_0 */
u_int32_t filler_13[9];
u_int8_t stripe_sectors;
u_int8_t filler_14[3];
u_int8_t array_width;
u_int8_t filler_15[3];
u_int32_t filler_16;
u_int8_t filler_17;
u_int8_t disk_number;
u_int32_t disk_sectors;
u_int16_t filler_18;
u_int32_t dummy_7[4];
u_int32_t filler_20[104];
} __packed;
/* LSILogic V2 MegaRAID Metadata */
#define LSIV2_LBA(dev) \
(((struct ad_softc *)device_get_ivars(dev))->total_secs - 1)
struct lsiv2_raid_conf {
u_int8_t lsi_id[6];
#define LSIV2_MAGIC "$XIDE$"
u_int8_t dummy_0;
u_int8_t flags;
u_int16_t version;
u_int8_t config_entries;
u_int8_t raid_count;
u_int8_t total_disks;
u_int8_t dummy_1;
u_int16_t dummy_2;
union {
struct {
u_int8_t type;
#define LSIV2_T_RAID0 0x01
#define LSIV2_T_RAID1 0x02
#define LSIV2_T_SPARE 0x08
u_int8_t dummy_0;
u_int16_t stripe_sectors;
u_int8_t array_width;
u_int8_t disk_count;
u_int8_t config_offset;
u_int8_t dummy_1;
u_int8_t flags;
#define LSIV2_R_DEGRADED 0x02
u_int32_t total_sectors;
u_int8_t filler[3];
} __packed raid;
struct {
u_int8_t device;
#define LSIV2_D_MASTER 0x00
#define LSIV2_D_SLAVE 0x01
#define LSIV2_D_CHANNEL0 0x00
#define LSIV2_D_CHANNEL1 0x10
#define LSIV2_D_NONE 0xff
u_int8_t dummy_0;
u_int32_t disk_sectors;
u_int8_t disk_number;
u_int8_t raid_number;
u_int8_t flags;
#define LSIV2_D_GONE 0x02
u_int8_t filler[7];
} __packed disk;
} configs[30];
u_int8_t disk_number;
u_int8_t raid_number;
u_int32_t timestamp;
u_int8_t filler[10];
} __packed;
/* LSILogic V3 MegaRAID Metadata */
#define LSIV3_LBA(dev) \
(((struct ad_softc *)device_get_ivars(dev))->total_secs - 4)
struct lsiv3_raid_conf {
u_int32_t magic_0; /* 0xa0203200 */
u_int32_t filler_0[3];
u_int8_t magic_1[4]; /* "SATA" */
u_int32_t filler_1[40];
u_int32_t dummy_0; /* 0x0d000003 */
u_int32_t filler_2[7];
u_int32_t dummy_1; /* 0x0d000003 */
u_int32_t filler_3[70];
u_int8_t magic_2[8]; /* "$_ENQ$31" */
u_int8_t filler_4[7];
u_int8_t checksum_0;
u_int8_t filler_5[512*2];
u_int8_t lsi_id[6];
#define LSIV3_MAGIC "$_IDE$"
u_int16_t dummy_2; /* 0x33de for OK disk */
u_int16_t version; /* 0x0131 for this version */
u_int16_t dummy_3; /* 0x0440 always */
u_int32_t filler_6;
struct {
u_int16_t stripe_pages;
u_int8_t type;
#define LSIV3_T_RAID0 0x00
#define LSIV3_T_RAID1 0x01
u_int8_t dummy_0;
u_int8_t total_disks;
u_int8_t array_width;
u_int8_t filler_0[10];
u_int32_t sectors;
u_int16_t dummy_1;
u_int32_t offset;
u_int16_t dummy_2;
u_int8_t device;
#define LSIV3_D_DEVICE 0x01
#define LSIV3_D_CHANNEL 0x10
u_int8_t dummy_3;
u_int8_t dummy_4;
u_int8_t dummy_5;
u_int8_t filler_1[16];
} __packed raid[8];
struct {
u_int32_t disk_sectors;
u_int32_t dummy_0;
u_int32_t dummy_1;
u_int8_t dummy_2;
u_int8_t dummy_3;
u_int8_t flags;
#define LSIV3_D_MIRROR 0x00
#define LSIV3_D_STRIPE 0xff
u_int8_t dummy_4;
} __packed disk[6];
u_int8_t filler_7[7];
u_int8_t device;
u_int32_t timestamp;
u_int8_t filler_8[3];
u_int8_t checksum_1;
} __packed;
/* Promise FastTrak Metadata */
#define PR_LBA(dev) \
(((struct ad_softc *)device_get_ivars(dev))->total_secs - 63)
#if 0
(((((struct ad_softc *)device_get_ivars(dev))->total_secs / (((struct ad_softc *)device_get_ivars(dev))->heads * ((struct ad_softc *)device_get_ivars(dev))->sectors)) * ((struct ad_softc *)device_get_ivars(dev))->heads * ((struct ad_softc *)device_get_ivars(dev))->sectors) - ((struct ad_softc *)device_get_ivars(dev))->sectors)
#endif
struct promise_raid_conf {
char promise_id[24];
#define PR_MAGIC "Promise Technology, Inc."
u_int32_t dummy_0;
u_int64_t magic_0;
#define PR_MAGIC0(x) (((u_int64_t)(x.channel) << 48) | \
((u_int64_t)(x.device != 0) << 56))
u_int16_t magic_1;
u_int32_t magic_2;
u_int8_t filler1[470];
struct {
u_int32_t integrity;
#define PR_I_VALID 0x00000080
u_int8_t flags;
#define PR_F_VALID 0x00000001
#define PR_F_ONLINE 0x00000002
#define PR_F_ASSIGNED 0x00000004
#define PR_F_SPARE 0x00000008
#define PR_F_DUPLICATE 0x00000010
#define PR_F_REDIR 0x00000020
#define PR_F_DOWN 0x00000040
#define PR_F_READY 0x00000080
u_int8_t disk_number;
u_int8_t channel;
u_int8_t device;
u_int64_t magic_0 __packed;
u_int32_t disk_offset;
u_int32_t disk_sectors;
u_int32_t rebuild_lba;
u_int16_t generation;
u_int8_t status;
#define PR_S_VALID 0x01
#define PR_S_ONLINE 0x02
#define PR_S_INITED 0x04
#define PR_S_READY 0x08
#define PR_S_DEGRADED 0x10
#define PR_S_MARKED 0x20
#define PR_S_FUNCTIONAL 0x80
u_int8_t type;
#define PR_T_RAID0 0x00
#define PR_T_RAID1 0x01
#define PR_T_RAID3 0x02
#define PR_T_RAID5 0x04
#define PR_T_SPAN 0x08
#define PR_T_JBOD 0x10
u_int8_t total_disks;
u_int8_t stripe_shift;
u_int8_t array_width;
u_int8_t array_number;
u_int32_t total_sectors;
u_int16_t cylinders;
u_int8_t heads;
u_int8_t sectors;
u_int64_t magic_1 __packed;
struct {
u_int8_t flags;
u_int8_t dummy_0;
u_int8_t channel;
u_int8_t device;
u_int64_t magic_0 __packed;
} disk[8];
} raid;
int32_t filler2[346];
u_int32_t checksum;
} __packed;
/* Silicon Image Medley Metadata */
#define SII_LBA(dev) \
( ((struct ad_softc *)device_get_ivars(dev))->total_secs - 1)
struct sii_raid_conf {
u_int16_t ata_params_00_53[54];
u_int64_t total_sectors;
u_int16_t ata_params_58_79[70];
u_int16_t dummy_0;
u_int16_t dummy_1;
u_int32_t controller_pci_id;
u_int16_t version_minor;
u_int16_t version_major;
u_int8_t timestamp[6]; /* BCD coded s:m:h:D:M:Y */
u_int16_t stripe_sectors;
u_int16_t dummy_2;
u_int8_t disk_number;
u_int8_t type;
#define SII_T_RAID0 0x00
#define SII_T_RAID1 0x01
#define SII_T_RAID01 0x02
#define SII_T_SPARE 0x03
u_int8_t raid0_disks;
u_int8_t raid0_ident;
u_int8_t raid1_disks;
u_int8_t raid1_ident;
u_int64_t rebuild_lba;
u_int32_t generation;
u_int8_t status;
#define SII_S_READY 0x01
u_int8_t base_raid1_position;
u_int8_t base_raid0_position;
u_int8_t position;
u_int16_t dummy_3;
u_int8_t name[16];
u_int16_t checksum_0;
int8_t filler1[190];
u_int16_t checksum_1; /* sum of all 128 shorts == 0 */
} __packed;