isw.c

/*
 * Intel Software RAID metadata format handler.
 *
 * Copyright (C) 2004-2008  Heinz Mauelshagen, Red Hat GmbH.
 *                          All rights reserved.
 *
 * Copyright (C) 2007,2008  Intel Corporation. All rights reserved.
 * November, 2007 - additions for Create, Delete, Rebuild & Raid 10.
 *
 * See file LICENSE at the top of this source tree for license information.
 */

/*
 * isw_read() etc. profited from Carl-Daniel Hailfinger's raiddetect code.
 *
 * Profited from the Linux 2.4 iswraid driver by
 * Boji Tony Kannanthanam and Martins Krikis.
 */
#define     HANDLER     "isw"

#include <time.h>
#include <math.h>
#include "internal.h"
#include <device/scsi.h>
#define     FORMAT_HANDLER
#include "isw.h"

#if   BYTE_ORDER != LITTLE_ENDIAN
#  define   DM_BYTEORDER_SWAB
#  include  <datastruct/byteorder.h>
#endif

#define     GB_DIV      1024/1024/2

static const char *handler = HANDLER;

/* Return minimum/maximum disks for a given RAID level. */
static uint16_t
_num_disks(uint8_t raid_level, int max)
{
      struct mm {
            uint8_t level;
            uint16_t min, max;
      };
      static struct mm mm[] = {
            {ISW_T_RAID0, 2, 6},
            {ISW_T_RAID1, 2, 2},
            {ISW_T_RAID10, 4, 4},
            {ISW_T_RAID5, 3, 6},
      };
      struct mm *m = ARRAY_END(mm);

      while (m-- > mm) {
            if (raid_level == m->level)
                  return max ? m->max : m->min;
      }

      return 1;
}

static inline uint16_t
min_num_disks(uint8_t raid_level)
{
      return _num_disks(raid_level, 0);
}

static inline uint16_t
max_num_disks(uint8_t raid_level)
{
      return _num_disks(raid_level, 1);
}

/* Check if given device belongs to a RAID10 mapping. */
static int
is_raid10(struct isw_dev *dev)
{
      return dev ? (dev->vol.map.raid_level == ISW_T_RAID10 ||
                  (dev->vol.map.raid_level == ISW_T_RAID1 &&
                   dev->vol.map.num_members >=
                   min_num_disks(ISW_T_RAID10))) : 0;
}

/* Find a disk table slot by serial number. */
static struct isw_disk *
_get_disk(struct isw *isw, struct dev_info *di)
{
      if (di->serial) {
            int i = isw->num_disks;
            struct isw_disk *disk = isw->disk;

            while (i--) {
                  if (!strncmp(di->serial, (const char *) disk[i].serial,
                             MAX_RAID_SERIAL_LEN))
                        return disk + i;
            }
      }

      return NULL;
}

static struct isw_disk *
get_disk(struct lib_context *lc, struct dev_info *di, struct isw *isw)
{
      struct isw_disk *disk;

      if ((disk = _get_disk(isw, di)))
            return disk;

      LOG_ERR(lc, NULL, "%s: Could not find disk %s in the metadata",
            handler, di->path);
}


enum name_type { N_PATH, N_NUMBER, N_VOLUME, N_VOLUME_FORCE };
static size_t
_name(struct lib_context *lc, struct isw *isw, char *str, size_t len,
      enum name_type nt, int num, struct isw_dev *dev, struct raid_dev *rd)
{
      struct {
            const char *fmt, *what;
      } formats[] = {
            {
            "isw_%u_%s", rd->di->path}, {
            "isw_%u", NULL}, {
            "isw_%u_%s", (const char *) dev->volume}, {
      "isw_%u_%s-%u", (const char *) dev->volume},}, *f = formats;

      if (nt < 0 || nt > N_VOLUME_FORCE)
            LOG_ERR(lc, 0, "unsupported name type");

      if (nt == N_VOLUME_FORCE)
            f += N_VOLUME;
      else {
            f += nt;
            if (nt == N_VOLUME)
                  f += (is_raid10(dev) ? 1 : 0);
      }

      return snprintf(str, len, f->fmt, isw->family_num, f->what, num);
}

static char *
name(struct lib_context *lc, struct raid_dev *rd,
     struct isw_dev *dev, enum name_type nt)
{
      size_t len;
      char *ret = NULL;
      int id = 0;
      struct isw *isw = META(rd, isw);
      struct isw_disk *disk = isw->disk;

      if (nt == N_VOLUME && is_raid10(dev)) {
            if ((disk = _get_disk(isw, rd->di))) {
                  int i = max_num_disks(ISW_T_RAID10);

                  while (i--) {
                        if (disk == isw->disk + i) {
                              id = i % 2;
                              goto ok;
                        }
                  }

                  return NULL;
            }
      }

      ok:
      if ((ret = alloc_private(lc, handler,
                         (len = _name(lc, isw, ret, 0, nt, id,
                                    dev, rd) + 1)))) {
            _name(lc, isw, ret, len, nt, id, dev, rd);
            len = snprintf(ret, 0, "%u", isw->family_num);
            mk_alpha(lc, ret + HANDLER_LEN, len);
      }
      else
            log_alloc_err(lc, handler);

      return ret;
}

/*
 * Retrieve status of device.
 *
 * FIXME: is this sufficient to cover all state ?
 */
static enum status
__status(unsigned status)
{
      return ((status & (CONFIGURED_DISK | USABLE_DISK)) &&
            !(FAILED_DISK & status)) ? s_ok : s_broken;
}

static enum status
status(struct lib_context *lc, struct raid_dev *rd)
{
      struct isw_disk *disk;

      if ((disk = get_disk(lc, rd->di, META(rd, isw))))
            return __status(disk->status);

      return s_undef;
}

/* Mapping of Intel types to generic types. */
static struct types types[] = {
      {ISW_T_RAID0, t_raid0},
      {ISW_T_RAID1, t_raid1},
      {ISW_T_RAID5, t_raid5_la},
      /* Only left asymmetric supported now.
         { ISW_T_RAID5, t_raid5_ls},
         { ISW_T_RAID5, t_raid5_ra},
         { ISW_T_RAID5, t_raid5_rs}, */
      {ISW_T_RAID10, t_raid1},
      {ISW_T_SPARE, t_spare},
      {ISW_T_UNDEF, t_undef},
};

static uint8_t
_get_raid_level(enum type raid_type)
{
      int i;

      for (i = 0;
           types[i].unified_type != t_undef &&
           types[i].unified_type != raid_type; i++);

      return types[i].type;
}

/* Neutralize disk type. */
static enum type
type(struct isw_dev *dev)
{

      if (is_raid10(dev))
            return t_raid1;

      return dev ? rd_type(types, (unsigned) dev->vol.map.raid_level) :
            t_group;
}

/*
 * Generate checksum of Raid metadata for mpb_size/sizeof(u32) words
 * (checksum field itself ignored for this calculation).
 */
static uint32_t
_checksum(struct isw *isw)
{
      uint32_t end = isw->mpb_size / sizeof(end),
            *p = (uint32_t *) isw, ret = 0;

      while (end--)
            ret += *p++;

      return ret - isw->check_sum;
}

/* Calculate next isw device offset. */
static struct isw_dev *
advance_dev(struct isw_dev *dev, struct isw_map *map, size_t add)
{
      return (struct isw_dev *) ((uint8_t *) dev +
                           (map->num_members - 1) *
                           sizeof(map->disk_ord_tbl) + add);
}

/* Advance to the next isw_dev from a given one. */
static struct isw_dev *
advance_raiddev(struct isw_dev *dev)
{
      struct isw_vol *vol = &dev->vol;
      struct isw_map *map = &vol->map;

      /* Correction: yes, it sits here! */
      dev = advance_dev(dev, map, sizeof(*dev));

      if (vol->migr_state)
            /* Need to add space for another map. */
            dev = advance_dev(dev, map, sizeof(*map));

      return dev;
}

/* Return isw_dev by table index. */
static struct isw_dev *
raiddev(struct isw *isw, unsigned i)
{
      struct isw_dev *dev = (struct isw_dev *) (isw->disk + isw->num_disks);

      while (i--)
            dev = advance_raiddev(dev);

      return dev;
}

/*
 * Read an Intel RAID device
 */
/* Endianess conversion. */
enum convert { FULL, FIRST, LAST };
#if   BYTE_ORDER == LITTLE_ENDIAN
#  define   to_cpu(x, y)
#else
/*
 * We can differ from the read_raid_dev template here,
 * because we don't get called from there.
 */
static void
to_cpu(struct isw *isw, enum convert cvt)
{
      unsigned i, j;
      struct isw_disk *dsk;
      struct isw_dev *dev;

      if (cvt == FIRST || cvt == FULL) {
            CVT32(isw->check_sum);
            CVT32(isw->mpb_size);
            CVT32(isw->family_num);
            CVT32(isw->generation_num);
      }

      if (cvt == FIRST)
            return;

      for (dsk = isw->disk; dsk < &isw->disk[isw->num_disks]; dsk++) {
            CVT32(dsk->totalBlocks);
            CVT32(dsk->scsiId);
            CVT32(dsk->status);
      }

      for (i = 0; i < isw->num_raid_devs; i++) {
            dev = raiddev(isw, i);

            /* RAID device. */
            CVT32(dev->SizeLow);
            CVT32(dev->SizeHigh);
            CVT32(dev->status);
            CVT32(dev->reserved_blocks);

            /* RAID volume has 8 bit members only. */

            /* RAID map. */
            CVT32(dev->vol.map.pba_of_lba0);
            CVT32(dev->vol.map.blocks_per_member);
            CVT32(dev->vol.map.num_data_stripes);
            CVT16(dev->vol.map.blocks_per_strip);

            for (j = 0; j < dev->vol.map.num_members; j++)
                  CVT16(dev->vol.map.disk_ord_tbl[j]);
      }
}
#endif

/* Return sector rounded size of isw metadata. */
static size_t
isw_size(struct isw *isw)
{
      return round_up(isw->mpb_size, ISW_DISK_BLOCK_SIZE);
}

/* Set metadata area size in bytes and config offset in sectors. */
static void
set_metadata_sizoff(struct raid_dev *rd, size_t size)
{
      rd->meta_areas->size = size;
      rd->meta_areas->offset = ISW_CONFIGSECTOR(rd->di) -
            size / ISW_DISK_BLOCK_SIZE + 1;
}

#define MIN_VOLUME_SIZE 204800
static void
enforce_size_limit(struct raid_set *rs)
{
      /* the min size is 100M bytes */
      if (rs->size && rs->size < MIN_VOLUME_SIZE)
            rs->size = MIN_VOLUME_SIZE;
}

static int
is_first_volume(struct lib_context *lc, struct raid_set *rs)
{
      struct raid_dev *rd1, *rd2;

      list_for_each_entry(rd1, &rs->devs, devs) {
            list_for_each_entry(rd2, LC_RD(lc), list) {
                  if (!strcmp(rd1->di->path, rd2->di->path) &&
                      rd1->fmt == rd2->fmt) {
                        /* No choice for the 2nd volume. */
                        rs->size = 0;
                        return 0;
                  }
            }
      }

      enforce_size_limit(rs);
      return 1;
}

/* Return correct signature version based on RAID type */
static char *
_isw_get_version(struct lib_context *lc, struct raid_set *rs)
{
      if((rs->total_devs == 5) || (rs->total_devs == 6))
            return mpb_versions[6]; /* MPB_VERSION_5OR6_DISK_ARRAY */

      if(rs->type == ISW_T_RAID5)
            return mpb_versions[5]; /* MPB_VERSION_RAID5 */

      if((rs->total_devs == 3) || (rs->total_devs == 4))
            return mpb_versions[4]; /* MPB_VERSION_3OR4_DISK_ARRAY */
      
      if(!is_first_volume(lc, rs))
            return mpb_versions[3]; /* MPB_VERSION_MUL_VOLS */

      if(rs->type == ISW_T_RAID1)
            return mpb_versions[2]; /* MPB_VERSION_RAID1 */

      if((rs->type == ISW_T_RAID0) || T_SPARE(rs))
            return mpb_versions[1]; /* MPB_VERSION_RAID0 */

      return mpb_versions[0]; /* unknown */
      
}

/* Check for isw signature (magic) and version. */
static int
is_isw(struct lib_context *lc, struct dev_info *di, struct isw *isw)
{
      if (strncmp((const char *) isw->sig, MPB_SIGNATURE, MPB_SIGNATURE_SIZE))
            return 0;

      /* Check version info; older versions supported. */
      if (strncmp((const char *) isw->sig + MPB_SIGNATURE_SIZE,
                MPB_VERSION_LAST, MPB_VERSION_LENGTH) > 0)
            log_print(lc,
                    "%s: untested metadata version %s found on %s",
                    handler, isw->sig + MPB_SIGNATURE_SIZE, di->path);

      return 1;
}

static void
isw_file_metadata(struct lib_context *lc, struct dev_info *di, void *meta)
{
      struct isw *isw = meta;
      /* Get the rounded up value for the metadata size */
      size_t size = isw_size(isw);

      file_metadata(lc, handler, di->path,
                  meta + (size / ISW_DISK_BLOCK_SIZE > 1 ?
                        ISW_DISK_BLOCK_SIZE : 0),
                  size, (di->sectors - (size / ISW_DISK_BLOCK_SIZE)) << 9);
      file_dev_size(lc, handler, di);
}

static int
isw_read_extended(struct lib_context *lc, struct dev_info *di,
              struct isw **isw, uint64_t * isw_sboffset, size_t * size)
{
      struct isw *isw_tmp;
      /* Get the rounded up value for the metadata blocks */
      size_t blocks = div_up((*isw)->mpb_size, ISW_DISK_BLOCK_SIZE);

      /* Allocate memory for the extended Intel superblock and read it in. */
      *size = blocks * ISW_DISK_BLOCK_SIZE;
      *isw_sboffset -= *size - ISW_DISK_BLOCK_SIZE;

      if ((isw_tmp = alloc_private(lc, handler, *size))) {
            /* Copy in first metadata sector. */
            memcpy(isw_tmp, *isw, ISW_DISK_BLOCK_SIZE);

            /* Read extended metadata to offset ISW_DISK_BLOCK_SIZE */
            if (blocks > 1 &&
                !read_file(lc, handler, di->path,
                         (void *) isw_tmp + ISW_DISK_BLOCK_SIZE,
                         *size - ISW_DISK_BLOCK_SIZE, *isw_sboffset)) {
                  dbg_free(isw_tmp);
                  isw_tmp = NULL;
            }
      }
      else
            return 0;

      dbg_free(*isw);
      *isw = isw_tmp;
      return *isw ? 1 : 0;
}

/* Check for RAID disk ok. */
static int
disk_ok(struct lib_context *lc, struct dev_info *di, struct isw *isw)
{
      struct isw_disk *disk = get_disk(lc, di, isw);

      return disk && __status(disk->status) == s_ok;
}

static void *
isw_read_metadata(struct lib_context *lc, struct dev_info *di,
              size_t * sz, uint64_t * offset, union read_info *info)
{
      size_t size = ISW_DISK_BLOCK_SIZE;
      uint64_t isw_sboffset = ISW_CONFIGOFFSET(di);
      struct isw *isw;

      if (!(isw = alloc_private_and_read(lc, handler, size,
                                 di->path, isw_sboffset)))
            goto out;

      /*
       * Convert start of metadata only, because we might need to
       * read extended metadata located ahead of it first.
       */
      to_cpu(isw, FIRST);

      /* Check Signature and read optional extended metadata. */
      if (!is_isw(lc, di, isw) ||
          !isw_read_extended(lc, di, &isw, &isw_sboffset, &size))
            goto bad;

      /*
       * Now that we made sure, that we've got all the
       * metadata, we can convert it completely.
       */
      to_cpu(isw, LAST);

      if (disk_ok(lc, di, isw)) {
            *sz = size;
            *offset = info->u64 = isw_sboffset;
            goto out;
      }

      bad:
      dbg_free(isw);
      isw = NULL;

      out:
      return (void *) isw;
}

static int setup_rd(struct lib_context *lc, struct raid_dev *rd,
                struct dev_info *di, void *meta, union read_info *info);
static struct raid_dev *
isw_read(struct lib_context *lc, struct dev_info *di)
{
      return read_raid_dev(lc, di, isw_read_metadata, 0, 0, NULL, NULL,
                       isw_file_metadata, setup_rd, handler);
}

/*
 * Write metadata to an Intel Software RAID device.
 */
static int
isw_write(struct lib_context *lc, struct raid_dev *rd, int erase)
{
      int ret;
      struct isw *isw = META(rd, isw);
      void *dst, *src = isw;
      uint32_t size = isw->mpb_size;

      to_disk(isw, FULL);

      /* Flip sectors for write_metadata() to work if extended metadata. */
      if (size > ISW_DISK_BLOCK_SIZE) {
            /* sunil */
            dst = alloc_private(lc, handler, 2 * ISW_DISK_BLOCK_SIZE);
            if (!dst)
                  return 0;

            memcpy(dst, src + ISW_DISK_BLOCK_SIZE, ISW_DISK_BLOCK_SIZE);
            memcpy(dst + ISW_DISK_BLOCK_SIZE, src, ISW_DISK_BLOCK_SIZE);
      }
      else
            dst = isw;
      rd->meta_areas->area = dst;
      ret = write_metadata(lc, handler, rd, -1, erase);
      rd->meta_areas->area = isw;

      if (dst != isw)
            dbg_free(dst);

      to_cpu(isw, FULL);
      return ret;
}

/*
 * Group an Intel SW RAID disk into potentially
 * multiple RAID sets and RAID disks.
 */
/* Check state if isw device map. */
static int
_check_map_state(struct lib_context *lc, struct raid_dev *rd,
             struct isw_dev *dev)
{
      /* FIXME: FAILED_MAP etc. */
      switch (dev->vol.map.map_state) {
      case ISW_T_STATE_NORMAL:
      case ISW_T_STATE_UNINITIALIZED:
      case ISW_T_STATE_DEGRADED:
      case ISW_T_STATE_FAILED:
            break;

      default:
            LOG_ERR(lc, 0,
                  "%s: unsupported map state 0x%x on %s for %s",
                  handler, dev->vol.map.map_state, rd->di->path,
                  (char *) dev->volume);
      }

      return 1;
}

/* Create a RAID device to map a volumes segment. */
static struct raid_dev *
_create_rd(struct lib_context *lc,
         struct raid_dev *rd, struct isw *isw, struct isw_dev *dev)
{
      struct raid_dev *r;

      if (!(r = alloc_raid_dev(lc, handler)))
            return NULL;

      if (!(r->meta_areas = alloc_meta_areas(lc, rd, handler, 1)))
            goto free;

      /* Configuration for spare disk. */
      if (isw->disk[0].status & SPARE_DISK) {
            r->meta_areas->offset = rd->meta_areas->offset;
            r->meta_areas->size = rd->meta_areas->size;
            r->meta_areas->area =
                  alloc_private(lc, handler, rd->meta_areas->size);
            memcpy(r->meta_areas->area, rd->meta_areas->area,
                   rd->meta_areas->size);

            r->type = t_spare;
            if (!(r->name = name(lc, rd, NULL, N_PATH)))
                  goto free;

            r->di = rd->di;
            r->fmt = rd->fmt;
            r->sectors = ISW_CONFIGSECTOR(r->di);
            goto out;
      }

      if (!_check_map_state(lc, rd, dev))
            goto free;

      if (!(r->private.ptr = alloc_private(lc, handler, sizeof(*dev))))
            goto free;

      memcpy(r->private.ptr, dev, sizeof(*dev));

      r->meta_areas->offset = rd->meta_areas->offset;
      r->meta_areas->size = rd->meta_areas->size;
      r->meta_areas->area = alloc_private(lc, handler, rd->meta_areas->size);
      memcpy(r->meta_areas->area, rd->meta_areas->area, rd->meta_areas->size);

      if ((r->type = type(dev)) == t_undef) {
            log_err(lc, "%s: RAID type %u not supported",
                  handler, (unsigned) dev->vol.map.raid_level);
            goto free;
      }

      if (!(r->name = name(lc, rd, dev, N_VOLUME)))
            goto free;

      r->di = rd->di;
      r->fmt = rd->fmt;
      r->offset = dev->vol.map.pba_of_lba0;
      if ((r->sectors = dev->vol.map.blocks_per_member - RAID_DS_JOURNAL))
            goto out;

      log_zero_sectors(lc, rd->di->path, handler);

      free:
      free_raid_dev(lc, &r);
      out:
      return r;
}

/* Find an Intel RAID set or create it. */
static void
create_rs(struct raid_set *rs, void *private)
{
      rs->stride = ((struct isw_dev *) private)->vol.map.blocks_per_strip;
}

/* Decide about ordering sequence of RAID device. */
static int
dev_sort(struct list_head *pos, struct list_head *new)
{
      struct isw *isw = RD(new)->private.ptr;

      return _get_disk(isw, RD(new)->di) < _get_disk(isw, RD(pos)->di);
}

static void
super_created(struct raid_set *super, void *private)
{
      super->type = t_raid0;
      super->stride = ((struct isw_dev *) private)->vol.map.blocks_per_strip;
}

/*
 * rs_group contains the top-level group RAID set (type: t_group) on entry
 * and shall be returned on success (or NULL on error).
 */
static struct raid_set *
group_rd(struct lib_context *lc,
       struct raid_set *rs_group, struct raid_dev *rd_meta)
{
      unsigned d;
      void *private;
      struct isw *isw = META(rd_meta, isw);
      struct isw_dev *dev;
      struct raid_dev *rd;
      struct raid_set *rs, *ss;
      char *ss_name = NULL;


      /* Configuration for spare disk. */
      if (isw->disk[0].status & SPARE_DISK) {

            /* Spare disk has no device description. */
            dev = NULL;
            if (!(rd = _create_rd(lc, rd_meta, isw, dev)))
                  return NULL;

            if (!(rs = find_or_alloc_raid_set(lc, rd->name,
                                      FIND_ALL, rd,
                                      &rs_group->sets, NULL,
                                      NULL))) {
                  free_raid_dev(lc, &rd);
                  return NULL;
            }

            rs->status = s_ok;
            list_add_sorted(lc, &rs->devs, &rd->devs, dev_sort);
      }
      else {
            /* Loop the device/volume table. */
            for (d = 0; d < isw->num_raid_devs; d++) {
                  dev = raiddev(isw, d);

                  if (!(rd = _create_rd(lc, rd_meta, isw, dev)))
                        return NULL;
                  if (is_raid10(dev)) {
                        ss_name = name(lc, rd, dev, N_VOLUME_FORCE);
                        ss = find_or_alloc_raid_set(lc, ss_name,
                                              FIND_ALL, rd,
                                              &rs_group->sets,
                                              super_created, dev);

                        if (!ss) {
                              dbg_free(ss_name);
                              free_raid_dev(lc, &rd);
                              return NULL;
                        }
                  }
                  else
                        ss = rs_group;

                  if (!(rs = find_or_alloc_raid_set(lc, rd->name,
                                            FIND_ALL, rd,
                                            &ss->sets, create_rs,
                                            dev))) {
                        free_raid_dev(lc, &rd);
                        return NULL;
                  }

                  rs->status = s_ok;

                  /* Save and set to enable dev_sort(). */
                  private = rd->private.ptr;
                  rd->private.ptr = isw;
                  list_add_sorted(lc, &rs->devs, &rd->devs, dev_sort);
                  /* Restore. */
                  rd->private.ptr = private;

            }
      }

      return rs_group;
}

/* Add an Intel SW RAID device to a set */
static struct raid_set *
isw_group(struct lib_context *lc, struct raid_dev *rd_meta)
{
      struct raid_set *rs_group = NULL;


      /*
       * Once we get here, an Intel SW RAID disk containing a metadata area
       * with a volume table has been discovered by isw_read. There is one
       * goup RAID set for each metadata configuration. The volume defined in
       * the metadata is a subset of the group RAID set.
       */

      /* Check if a top level group RAID set already exists. */
      if (!(rs_group =
            find_or_alloc_raid_set(lc, rd_meta->name, FIND_TOP, rd_meta,
                             LC_RS(lc), NO_CREATE, NO_CREATE_ARG)))
            return NULL;


      /*
       * Add the whole underlying (meta) RAID device to the group set.
       * Sorting is no problem here, because RAID sets and devices will
       * be created for all the Volumes of an ISW set and those need sorting.
       */
      rd_meta->private.ptr = rd_meta->meta_areas->area;
      list_add_sorted(lc, &rs_group->devs, &rd_meta->devs, dev_sort);
      rd_meta->private.ptr = NULL;


      /* mark spare set as group set */
      if (T_SPARE(rs_group))
            rs_group->type = t_group;



      /*
       * We need to run through the volume table and create a RAID set and
       * RAID devices hanging off it for every volume,
       * so that the activate code is happy.
       *
       * A pointer to the top-level group RAID set
       * gets returned or NULL on error.
       */
      struct raid_set *ret = group_rd(lc, rs_group, rd_meta);

      return ret;
}

static unsigned
adjust_length(struct isw_dev *dev, struct isw_dev *dev_rebuilt,
            unsigned map_size)
{
      return (dev == dev_rebuilt || !dev->vol.migr_state) ?
            map_size : 2 * map_size;
}

/*
 * Find out index of a raid device in isw_dev array by name.
 * The function returns -1 if no relevant device can be found.
 */
static int
rd_idx_by_name(struct isw *isw, const char *name)
{
      int i = isw->num_raid_devs;

      while (i--) {
            if (strstr(name, (const char *) raiddev(isw, i)->volume))
                  return i;
      }

      return -ENOENT;
}

/* Return RAID device for serial string. */
static struct raid_dev *
rd_by_serial(struct raid_set *rs, const char *serial)
{
      struct raid_dev *rd;

      list_for_each_entry(rd, &rs->devs, devs) {
            if (rd->di &&
                !strncmp(rd->di->serial, serial, MAX_RAID_SERIAL_LEN))
                  return rd;
      }

      return NULL;
}

static struct isw *
update_metadata_after_rebuild(struct lib_context *lc, struct raid_set *rs)
{
      struct raid_dev *rd = list_entry(rs->devs.next, struct raid_dev, devs);
      struct isw *old_isw = META(rd, isw), *new_isw;
      struct isw_dev *old_vol0 = NULL, *old_vol1 = NULL, *vol_rebuilt = NULL;
      int vol_rebuilt_idx;
      int remove_disk;
      unsigned map_size, new_isw_size;
      unsigned old_isw_offs, new_isw_offs;
      unsigned i;


      old_vol0 = raiddev(old_isw, 0);
      if (old_isw->num_raid_devs > 1)
            old_vol1 = raiddev(old_isw, 1);

      /* Determine the volume being rebuilt. */
      vol_rebuilt_idx =
            rd_idx_by_name(old_isw,
                         lc->options[LC_REBUILD_SET].arg.str +
                         strlen(rs->name) + 1);
      if (vol_rebuilt_idx < 0)
            return NULL;

      /* Modify metadata related to the volume being rebuilt. */
      vol_rebuilt = vol_rebuilt_idx ? old_vol1 : old_vol0;
      vol_rebuilt->vol.migr_type = 0;     /* FIXME: replace magic numbers */
      vol_rebuilt->vol.migr_state = 0;    /* FIXME: replace magic number */
      vol_rebuilt->vol.map.failed_disk_num = 255;     /* FIXME: replace magic number */

      /* Are we going to remove the failed disk from the metadata ? */
      remove_disk = (!old_vol0->vol.migr_type && old_vol1) ?
            !old_vol1->vol.migr_type : 1;

      /* Calculate new metadata's size and allocate memory for it. */
      map_size = sizeof(struct isw_map) +
            (vol_rebuilt->vol.map.num_members - 1) *
            sizeof(((struct isw_map *) NULL)->disk_ord_tbl);

      /* If we remove a disk. */
      new_isw_size = old_isw->mpb_size -  /* old size */
            remove_disk * sizeof(struct isw_disk) - map_size;
      new_isw = alloc_private(lc, handler, new_isw_size);

      /* Copy metadata structures: struct isw without disks' array. */
      new_isw_offs = old_isw_offs = i =
            sizeof(struct isw) - sizeof(struct isw_disk);
      memcpy(new_isw, old_isw, i);

      /* Copy metadata structures: disks' array. */
      i = (old_isw->num_disks - remove_disk) * sizeof(struct isw_disk);
      memcpy((void *) new_isw + new_isw_offs,
             (void *) old_isw + old_isw_offs, i);
      new_isw_offs += i;
      old_isw_offs += i + remove_disk * sizeof(struct isw_disk);

      /* Copy metadata structures: isw_dev record #0. */
      i = sizeof(struct isw_dev) - sizeof(struct isw_map) +
            adjust_length(old_vol0, vol_rebuilt, map_size);

      memcpy((void *) new_isw + new_isw_offs,
             (void *) old_isw + old_isw_offs, i);
      new_isw_offs += i;
      old_isw_offs += i;
      if (old_vol0 == vol_rebuilt)
            old_isw_offs += map_size;

      /* Copy metadata structures: isw_dev record #1 (if present). */
      if (old_vol1) {
            i = sizeof(struct isw_dev) - sizeof(struct isw_map) +
                  adjust_length(old_vol1, vol_rebuilt, map_size);
            memcpy((void *) new_isw + new_isw_offs,
                   (void *) old_isw + old_isw_offs, i);
            new_isw_offs += i;
            old_isw_offs += i;

            if (old_vol1 == vol_rebuilt)
                  old_isw_offs += map_size;
      }

      /* finally update new metadata's fields */
      new_isw->mpb_size = new_isw_size;
      new_isw->num_disks -= remove_disk;
      new_isw->generation_num++;
      new_isw->check_sum = _checksum(new_isw);
      return new_isw;
}


/* Handle rebuild state. */
static int
get_rebuild_state(struct lib_context *lc,
              struct raid_set *rs, struct raid_dev *rd)
{
      int idx;
      struct raid_dev *check_rd;
      struct isw *isw;
      struct isw_dev *dev;
      struct isw_disk *disk;

      list_for_each_entry(check_rd, &rs->devs, devs) {
            if (check_rd->meta_areas) {
                  isw = META(check_rd, isw);

                  idx = rd_idx_by_name(isw,
                                   lc->options[LC_REBUILD_SET].
                                   arg.str);
                  if (idx < 0)
                        return 0;

                  dev = raiddev(isw, idx);
                  disk = isw->disk;

                  if (dev->vol.migr_state &&
                      dev->vol.migr_type &&
                      dev->vol.map.failed_disk_num < isw->num_disks) {
                        /*
                         * If rd that belongs to RAID set is
                         * pointed at by failed disk number 
                         * the RAID set state is migration.
                         */
                        rd = rd_by_serial(rs,
                                      (const char *) disk[dev->
                                                      vol.map.failed_disk_num].serial);
                        if (rd)
                              /*
                               * Found RAID device that belongs to
                               * RAID set is marked as failed in
                               * metadata.
                               */
                              return s_nosync;
                  }
                  else if (dev->vol.map.map_state == ISW_T_STATE_DEGRADED)
                        return s_inconsistent;
            }

            /*
             * Check only first metadata on the
             * first rd that has a metadata.
             */
            return s_inconsistent;

      }

      return s_inconsistent;
}

/* isw metadata handler routine. */
static int
isw_metadata_handler(struct lib_context *lc, enum handler_commands command,
                 struct handler_info *info, void *context)
{
      int idx, ret = 0;
      struct raid_set *rs = context;
      struct raid_dev *rd = list_entry(rs->devs.next, struct raid_dev, devs);
      struct isw *isw, *new_isw;
      struct isw_dev *dev;
      struct isw_disk *disk;

      switch (command) {
      case UPDATE_REBUILD_STATE:
            new_isw = update_metadata_after_rebuild(lc, rs);
            if (!new_isw)
                  return 0;

            /* Embed the new metadata on disks. */
            list_for_each_entry(rd, &rs->devs, devs) {
                  set_metadata_sizoff(rd, isw_size(new_isw));
                  memcpy(rd->meta_areas->area, new_isw,
                         new_isw->mpb_size);

                  /* FIXME: use fmt->write from metadata.c instead ? */
                  /* FIXME: log update. */
                  ret = isw_write(lc, rd, 0);
                  if (!ret)
                        break;
            }

            break;

      case GET_REBUILD_STATE:
            return get_rebuild_state(lc, rs, rd);

      case GET_REBUILD_DRIVE:
            isw = META(rd, isw);
            dev = raiddev(isw, 0);
            disk = isw->disk + dev->vol.map.failed_disk_num;

            rd = rd_by_serial(rs, (const char *) disk->serial);
            if (rd) {
                  if (info && info->data.str && info->size) {
                        strncpy(info->data.str, rd->di->path,
                              info->size);
                        log_print(lc,
                                "Rebuild Drive: %s Serial No: %s\n",
                                rd->di->path, rd->di->serial);
                        ret = 1;
                  }
                  else
                        log_err(lc,
                              "Can't provide rebuild drive path!");
            }

            break;

      case GET_REBUILD_DRIVE_NO:
            rd = list_entry(rs->devs.next, typeof(*rd), devs);
            isw = META(rd, isw);
            idx = rd_idx_by_name(isw, lc->options[LC_REBUILD_SET].arg.str);
            if (idx < 0)
                  return 0;

            dev = raiddev(isw, idx);
            disk = isw->disk;

            if (info) {
                  if (dev->vol.map.failed_disk_num <
                      dev->vol.map.num_members) {
                        info->data.i32 = is_raid10(dev) ?
                              dev->vol.map.failed_disk_num /
                              dev->vol.map.num_domains :
                              dev->vol.map.failed_disk_num;

                        ret = 1;
                  }
                  else
                        info->data.i32 = -1;
            }

            break;            /* case GET_REBUILD_DRIVE_NO */

      default:
            LOG_ERR(lc, 0, "%u not yet supported", command);

      }

      return ret;
}

/*
 * Check an Intel SW RAID set.
 *
 * FIXME: more sanity checks.
 */
static unsigned
devices(struct raid_dev *rd, void *context)
{
      return rd->type != t_spare ?
            ((struct isw_dev *) rd->private.ptr)->vol.map.num_members : 0;
}

static unsigned
devices_per_domain(struct raid_dev *rd, void *context)
{
      return ((struct isw_dev *) rd->private.ptr)->vol.map.num_members /
            ((struct isw_dev *) rd->private.ptr)->vol.map.num_domains;
}

static int
check_rd(struct lib_context *lc, struct raid_set *rs,
       struct raid_dev *rd, void *context)
{
      struct isw_dev *dev = rd->private.ptr;

      /* FIXME: more status checks ? */
      if (dev->status) {
            LOG_ERR(lc, 0, "%s device for volume \"%s\" broken on %s "
                  "in RAID set \"%s\"",
                  handler, dev->volume, rd->di->path, rs->name);

      }

      return 1;
}

static int
_isw_check(struct lib_context *lc, struct raid_set *rs)
{
      struct raid_set *r;

      list_for_each_entry(r, &rs->sets, list) {
            if (SETS(r))
                  check_raid_set(lc, r, devices_per_domain, NULL,
                               check_rd, NULL, handler);
            else
                  check_raid_set(lc, r, devices, NULL, check_rd,
                               NULL, handler);
      }

      return 1;
}

static char *
get_rs_basename(char *str)
{
      char *ret, *end;

      if (!(end = strchr(str, '_')))
            return str;

      if (!(end = strchr((++end), '_')))
            return str;

      if ((ret = strstr(str, "isw_")) == str && strlen(end) > 1)
            return ++end;

      return str;
}

/* Check that volume name is unique. */
static int
is_name_unique(struct lib_context *lc, struct raid_set *rs)
{
      struct raid_set *rs1, *rs2;
      char *bn;

      list_for_each_entry(rs1, LC_RS(lc), list) {
            if (rs1->type == t_group) {
                  list_for_each_entry(rs2, &rs1->sets, list) {
                        bn = get_rs_basename(rs2->name);
                        if (!strcmp(bn, rs->name))
                              goto out_used;
                  }
            }
            else {
                  bn = get_rs_basename(rs1->name);
                  if (!strcmp(bn, rs->name))
                        goto out_used;
            }
      }

      return 1;

      out_used:
      log_dbg(lc, "%s is being used", bn);
      return 0;
}

static int
check_capability(struct raid_set *rs)
{
      uint8_t raid_level = _get_raid_level(rs->type);

      if (SETS(rs)) {
            struct raid_set *rs1 =
                  list_entry(rs->sets.next, struct raid_set, list);

            if (raid_level == ISW_T_RAID0 && rs1->type == t_raid1)
                  raid_level = ISW_T_RAID10;
            else
                  raid_level = ISW_T_UNDEF;
      }

      return raid_level;
}

static int
match_hd_array(struct raid_set *rs, struct isw *isw)
{
      int broken = 0, found = 0; // , i = isw->num_disks;
//    struct isw_disk *disk = isw->disk;
      struct raid_dev *rd;

/* FIXME: all disks broken in case of no SCSI IDs
      while (i--) {
            if (disk[i].scsiId == UNKNOWN_SCSI_ID)
                  broken++;
      }
*/

      list_for_each_entry(rd, &rs->devs, devs) {
            if (_get_disk(isw, rd->di))
                  found++;
      }

      return isw->num_disks == broken + found && found == rs->total_devs;
}

static int
is_hd_array_available(struct lib_context *lc, struct raid_set *rs)
{
      struct raid_dev *rd1, *rd2;

      list_for_each_entry(rd1, &rs->devs, devs) {
            list_for_each_entry(rd2, LC_RD(lc), list) {
                  if (!strcmp(rd1->di->path, rd2->di->path) &&
                      rd1->fmt == rd2->fmt)
                        return match_hd_array(rs, META(rd2, isw));
            }
      }

      return 0;
}

/* Retrieve and make up SCSI ID. */
static unsigned
get_scsiId(struct lib_context *lc, char *path)
{
      int fd;
      Sg_scsi_id sg_id;

      memset(&sg_id, 0, sizeof(sg_id));

      if ((fd = open(path, O_RDONLY)) == -1)
            return UNKNOWN_SCSI_ID;

      if (!get_scsi_id(lc, fd, &sg_id)) {
            close(fd);
            return UNKNOWN_SCSI_ID;
      }

      close(fd);
      return (sg_id.host_no << 16) | (sg_id.scsi_id << 8) | sg_id.lun;
}

static int
isw_config_disks(struct lib_context *lc, struct isw_disk *disk,
             struct raid_set *rs)
{
      int i = 0;
      struct raid_dev *rd;

      list_for_each_entry(rd, &rs->devs, devs) {
            strncpy((char *) disk[i].serial, rd->di->serial,
                  MAX_RAID_SERIAL_LEN);
            disk[i].totalBlocks = rd->di->sectors;

            /* FIXME: when scsiID == UNKNOWN_SCSI_ID */
            disk[i].scsiId = get_scsiId(lc, rd->di->path);
            disk[i++].status = CLAIMED_DISK |
                  CONFIG_ON_DISK |
                  DETECTED_DISK | USABLE_DISK |
                  DISK_SMART_EVENT_SUPPORTED |
                  ((rs->type == ISW_T_SPARE) ?
                   SPARE_DISK : CONFIGURED_DISK);
      }

      return i;
}

static void
isw_config_vol(struct raid_set *rs, struct isw_vol *vol)
{
      if (rs->status == s_init) {
            vol->migr_state = 0;
            vol->migr_type = 0;
      }
}

static uint32_t
_get_stride_size(struct raid_set *rs)
{
      /* In blocks (512-bytes). */
      /* First member is default stride size. */
      static const uint32_t s_raid0[] = { 256, 8, 16, 32, 64, 128, 256, 0 };
      static const uint32_t s_raid1[] = { 128, 128, 0 };
      static const uint32_t s_raid10[] = { 128, 8, 16, 32, 64, 128, 256, 0 };
      static const uint32_t s_raid5[] = { 128, 32, 64, 128, 256, 0 };
      struct strip_options {
            const uint8_t level;
            const uint32_t *options;
      };
      static struct strip_options strip_options[] = {
            {ISW_T_RAID0, s_raid0},
            {ISW_T_RAID1, s_raid1},
            {ISW_T_RAID10, s_raid10},
            {ISW_T_RAID5, s_raid5},
      };
      struct strip_options *so = ARRAY_END(strip_options);

      while (so-- > strip_options) {
            if (rs->type == so->level) {
                  int i;

                  if (rs->stride) {
                        i = 1;
                        while (so->options[i + 1] &&
                               rs->stride > so->options[i])
                              i++;
                  }
                  else
                        i = 0;

                  return so->options[i];
            }
      }

      return 0;
}

static void
_find_factors(struct raid_set *rs, uint8_t * div, uint8_t * sub)
{
      struct factors {
            const uint8_t level;
            const uint8_t div, sub;
      };
      static struct factors factors[] = {
            {ISW_T_RAID0, 1, 0},
            {ISW_T_RAID1, 2, 0},
            {ISW_T_RAID10, 2, 0},
            {ISW_T_RAID5, 1, 1},
      };
      struct factors *f = ARRAY_END(factors);

      while (f-- > factors) {
            if (rs->type == f->level) {
                  *div = f->div;
                  *sub = f->sub;
                  return;
            }
      }

      *div = 1;
      *sub = 0;
}

/* Configure an isw map. */
static void
isw_config_map(struct raid_set *rs, struct isw_map *map,
             uint64_t size, uint32_t first)
{
      int i;
      uint8_t div, sub;

      _find_factors(rs, &div, &sub);
      map->pba_of_lba0 = first;
      map->blocks_per_strip = _get_stride_size(rs);
      map->num_data_stripes = ((size/map->blocks_per_strip) + (rs->total_devs -sub -1)) / (rs->total_devs-sub); 
      map->blocks_per_member = (map->blocks_per_strip * map->num_data_stripes) * div +
            RAID_DS_JOURNAL;

      map->map_state = ISW_T_STATE_NORMAL;
      map->raid_level = rs->type == ISW_T_RAID10 ? ISW_T_RAID1 : rs->type;
      map->num_members = rs->found_devs;
      map->num_domains = (rs->type == ISW_T_RAID1 ||
                      rs->type == ISW_T_RAID10) ? 2 : 1;
      map->failed_disk_num = ISW_DEV_NONE_FAILED;
      map->ddf = 1; 

/* FIXME */
      for (i = 0; i < map->num_members; i++)
            map->disk_ord_tbl[i] = i;
}

/* Calculate the (new) array size. */
static uint64_t
_cal_array_size(struct isw_disk *disk, struct raid_set *rs, struct isw_dev *dev)
{
      int n = 0;
      uint8_t div, sub;
      uint64_t min_ds = ~0, max_ds;
      struct raid_dev *rd;

      list_for_each_entry(rd, &rs->devs, devs) {
            if (min_ds > rd->di->sectors)
                  min_ds = rd->di->sectors;
            n++;
      }

      if (min_ds < DISK_RESERVED_BLOCKS)
            return 0;

      min_ds -= DISK_RESERVED_BLOCKS;

      /* blank disks */
      if (dev) {
            /* One volume existed and started from the beginning */
            if (!dev->vol.map.pba_of_lba0) {
                  max_ds = dev->vol.map.blocks_per_member +
                        DISK_RESERVED_BLOCKS;

                  if (min_ds > max_ds)
                        min_ds -= max_ds;
                  else
                        return 1;
                  /* An existing volume at the bottom */
            }
            else if (dev->vol.map.pba_of_lba0 >=
                   RAID_VOLUME_RESERVED_BLOCKS)
                  min_ds = dev->vol.map.pba_of_lba0 -
                        RAID_VOLUME_RESERVED_BLOCKS;
            else
                  return 1;
      }
      else {
            if (min_ds > DISK_RESERVED_BLOCKS)
                  min_ds -= DISK_RESERVED_BLOCKS;
            else
                  return 1;
      }

      _find_factors(rs, &div, &sub);
      max_ds = min_ds * (n - sub) / div;
      return max_ds;
}

#define METADATA_BLOCKS 2
static int
isw_config_dev(struct lib_context *lc, struct raid_set *rs,
             struct isw_dev *dev1, struct isw_dev *dev2, uint64_t max_size)
{
      uint64_t tmp = rs->size ? rs->size : max_size;

      strncpy((char *) dev2->volume, rs->name, MAX_RAID_SERIAL_LEN);
      dev2->SizeLow = (uint32_t) tmp;
      dev2->SizeHigh = (uint32_t) (tmp >> 32);
      /* FIXME: isi this status ok, Radoslaw ? */
      dev2->status = ISW_DEV_READ_COALESCING | ISW_DEV_WRITE_COALESCING;
      isw_config_vol(rs, &dev2->vol);

      if (!dev1) {
            isw_config_map(rs, &dev2->vol.map, tmp, 0);
            return 1;
      }

      if (!dev1->vol.map.pba_of_lba0)     /* Start at the begginning. */
            isw_config_map(rs, &dev2->vol.map, tmp,
                         dev1->vol.map.blocks_per_member +
                         MIGR_OPT_SPACE);
      else {
            isw_config_map(rs, &dev2->vol.map, tmp, 0);

            if (dev2->vol.map.blocks_per_member + MIGR_OPT_SPACE >
                dev1->vol.map.pba_of_lba0)
                  LOG_ERR(lc, 0, "%s: not enough space to create "
                        "requested volume", handler);

      }

      return 1;
}

static void
display_new_volume(struct raid_set *rs, struct isw *isw, struct isw_dev *dev)
{
      enum type rt;
      const char *type_name = NULL;
      struct raid_dev *r;

      if (rs->type == ISW_T_SPARE) {      /* Case if spare disk. */
            printf("\n\n     Create a SPARE DISK with ISW metadata "
                   "format     \n\nDISK:     ");
      }
      else {
            rt = type(dev);
            switch (rt) {
            case t_raid0:
                  type_name = "RAID0";
                  break;

            case t_raid1:
                  type_name = dev->vol.map.num_members ==
                        min_num_disks(ISW_T_RAID10) ?
                        "RAID01 (isw RAID10)" : "RAID1";
                  break;

            case t_raid5_la:
                  type_name = "RAID5";
                  break;

            default:
                  return;
            }

            printf("\n\n     Create a RAID set with ISW "
                   "metadata format     \n\n");
            printf("RAID name:      %s\n", dev->volume);
            printf("RAID type:      %s\n", type_name);
            printf("RAID size:      %lluG",
                   ((unsigned long long) dev->SizeLow +
                  ((unsigned long long) dev->SizeHigh << 32)) / GB_DIV);
            printf(" (%llu blocks)\n",
                   ((unsigned long long) dev->SizeLow +
                  ((unsigned long long) dev->SizeHigh << 32)));

            if (rt != t_raid1)
                  printf("RAID strip:     %uk (%u blocks)\n",
                         dev->vol.map.blocks_per_strip / 2,
                         dev->vol.map.blocks_per_strip);

            printf("DISKS:     ");
      }

      list_for_each_entry(r, &rs->devs, devs) {
            if (_get_disk(isw, r->di))
                  printf("%s%s ", r->di->path,
                         rs->type == ISW_T_SPARE ? "" : ",");
      }

      printf("\n\n\n");
}

static struct isw *
_isw_create_first_volume(struct lib_context *lc, struct raid_set *rs)
{

      uint16_t isw_size;
      uint64_t total_size;
      struct isw *isw;
      struct isw_dev *dev = NULL;
      struct isw_disk *disk = NULL;
      char *sig_version;

      total_size = _cal_array_size(disk, rs, NULL);
      if (rs->size > total_size)
            LOG_ERR(lc, 0,
                  "%s: the size exceeds the max %lluG (%llu blocks)",
                  handler, total_size / GB_DIV, total_size);

      /* allocate min 2 sectors space for isw metadata. */
      isw_size = METADATA_BLOCKS * ISW_DISK_BLOCK_SIZE;
      if (!(isw = alloc_private(lc, handler, isw_size)))
            LOG_ERR(lc, 0, "%s: failed to allocate memory", handler);

      disk = isw->disk;
      isw->num_disks = isw_config_disks(lc, disk, rs);
      isw_size = sizeof(*isw) + sizeof(*disk) * (isw->num_disks - 1);

      if (rs->type != ISW_T_SPARE) {
            dev = (struct isw_dev *) (disk + isw->num_disks);
            if (!isw_config_dev(lc, rs, NULL, dev, total_size)) {
                  dbg_free(isw);
                  return NULL;
            }

            isw_size += sizeof(*dev) + sizeof(dev->vol.map.disk_ord_tbl) *
                  (isw->num_disks - 1);
      }

      display_new_volume(rs, isw, dev);

      strncpy((char *) isw->sig, MPB_SIGNATURE, MPB_SIGNATURE_SIZE);
      sig_version = _isw_get_version(lc, rs);
      strncpy((char *) isw->sig + MPB_SIGNATURE_SIZE,
            sig_version, MPB_VERSION_LENGTH);
      isw->mpb_size = isw_size;
      isw->generation_num = 0;
      isw->attributes = MPB_ATTRIB_CHECKSUM_VERIFY;
      isw->num_raid_devs = (rs->type == ISW_T_SPARE) ? 0 : 1;
      isw->family_num = isw->orig_family_num = _checksum(isw) + time(NULL);
      isw->check_sum = 0;
      isw->check_sum = _checksum(isw);
      return isw;
}

static struct raid_set *
_find_group(struct lib_context *lc, struct raid_set *rs)
{
      struct raid_set *r;
      struct raid_dev *rd1, *rd2;
      int match = 0;

      list_for_each_entry(r, LC_RS(lc), list) {
            if (r->type != t_group)
                  continue;

            list_for_each_entry(rd2, &rs->devs, devs) {
                  list_for_each_entry(rd1, &r->devs, devs) {
                        if (!strcmp(rd1->di->path, rd2->di->path)) {
                              match++;
                              break;
                        }
                  }
            }

            if (match) {
                  if (match == rs->found_devs)
                        return r;

                  LOG_ERR(lc, NULL,
                        "%s: mismatch in the number of drives "
                        "found", handler);
            }
      }

      return NULL;
}

static struct isw *
_isw_create_second_volume(struct lib_context *lc, struct raid_set *rs)
{
      uint16_t isw_size;
      uint64_t total_size;
      struct raid_set *rs_group;
      struct raid_dev *rd;
      struct isw *isw, *isw_v1;
      struct isw_dev *dev1, *dev2;
      char *sig_version; 

      if (!(rs_group = _find_group(lc, rs)))
            return NULL;

      rd = list_entry(rs_group->devs.next, struct raid_dev, devs);
      /* Note: size of a volume data structure is smaller than a sector. */

      /* FIXME: >=2 ? */
      isw_v1 = rd->meta_areas->area;
      if (isw_v1->num_raid_devs >= 2)
            LOG_ERR(lc, NULL, "%s: only two volumes allowed per array",
                  handler);

      if (!(dev1 = raiddev(isw_v1, 0)))
            LOG_ERR(lc, NULL, "%s: failed to get the first volume info",
                  handler);

      total_size = _cal_array_size(isw_v1->disk, rs, dev1);
      if (total_size < MIN_VOLUME_SIZE)
            LOG_ERR(lc, NULL, "%s: either not enough disk space or the "
                  "requested volume size is too small", handler);

      isw_size = rd->meta_areas->size + ISW_DISK_BLOCK_SIZE;
      if (!(isw = alloc_private(lc, handler, isw_size)))
            LOG_ERR(lc, NULL, "%s: failed to allocate memory", handler);

      memcpy(isw, isw_v1, isw_size - ISW_DISK_BLOCK_SIZE);
      isw_size = isw_v1->mpb_size;
      dev2 = raiddev(isw, 1);
      if (!isw_config_dev(lc, rs, dev1, dev2, total_size)) {
            dbg_free(isw);
            return NULL;
      }

      isw_size += sizeof(*dev2) + sizeof(dev2->vol.map.disk_ord_tbl) *
            (isw->num_disks - 1);

      display_new_volume(rs, isw, dev2);

      /* If new signature version is higher than the old one, replace it */
      sig_version = _isw_get_version(lc, rs);
      if (strcmp((const char *) isw->sig + MPB_SIGNATURE_SIZE,
                (const char *) sig_version) < 0)
            strncpy((char *) isw->sig + MPB_SIGNATURE_SIZE,
                  sig_version, MPB_VERSION_LENGTH);       
      isw->mpb_size = isw_size;
      isw->generation_num++;
      isw->attributes = MPB_ATTRIB_CHECKSUM_VERIFY;
      isw->num_raid_devs++;
      isw->check_sum = 0;
      isw->check_sum = _checksum(isw);
      return isw;
}

static struct isw_dev *
get_raiddev(struct isw *isw, char *name)
{
      struct isw_dev *dev;
      int i;

      for (i = 0; i < isw->num_raid_devs; i++) {
            dev = raiddev(isw, i);
            if (!strcmp((const char *) dev->volume, (const char *) name))
                  return dev;
      }

      return NULL;
}

/*
 * Update the metadata attached to each raid
 * device and the name of the RAID set.
 */
static int
update_raidset(struct lib_context *lc, struct raid_set *rs, struct isw *isw)
{
      int blocks = div_up(isw->mpb_size, ISW_DISK_BLOCK_SIZE);
      size_t size = blocks * ISW_DISK_BLOCK_SIZE;
      struct raid_dev *rd;
      struct isw_dev *dev;

      list_for_each_entry(rd, &rs->devs, devs) {
            if (rd->meta_areas) {
                  if (rd->meta_areas->area)
                        dbg_free(rd->meta_areas->area);

                  dbg_free(rd->meta_areas);
            }

            if (!(rd->meta_areas = alloc_meta_areas(lc, rd, handler, 1)))
                  return 0;

            if (!(rd->meta_areas->area = alloc_private(lc, handler, size)))
                  return 0;

            set_metadata_sizoff(rd, size);
            memcpy(rd->meta_areas->area, isw, size);
            rd->type = t_group;

            dev = NULL;
            if (rs->type != ISW_T_SPARE &&
                !(dev = get_raiddev(isw, rs->name)))
                  return 0;

            if (!(rd->name = name(lc, rd, dev, N_NUMBER)))
                  return 0;
      }

      if (rs->type != ISW_T_SPARE) {
            if (!(dev = get_raiddev(isw, rs->name)))
                  return 0;

            dbg_free(rs->name);
            rd = list_entry(rs->devs.next, struct raid_dev, devs);
            if (!(rs->name = name(lc, rd, dev, N_VOLUME)))
                  return 0;
      }

      return 1;
}

/* Create a RAID set (i.e. an isw volume). */
static int
_isw_create_raidset(struct lib_context *lc, struct raid_set *rs)
{
      uint16_t min, max = 0;
      struct isw *isw;

      /* The type is changed into the ISW defination */
      if ((rs->type = check_capability(rs)) == ISW_T_UNDEF)
            LOG_ERR(lc, 0, "%s: unsupported raid level", handler);

      if (rs->type != ISW_T_SPARE && rs->name) {
            if (!is_name_unique(lc, rs))
                  LOG_ERR(lc, 0, "%s: the name %s is already in use, "
                        "please try another name", handler, rs->name);
      }

      if ((min = min_num_disks(rs->type)) > rs->found_devs ||
          (max = max_num_disks(rs->type)) < rs->found_devs)
            LOG_ERR(lc, 0, "%s: the RAID set cannot have %s "
                  "than %d hard drives",
                  handler, max ? "more" : "less", max ? max : min);

      /*
       * The size of the RAID set is set to 0 if there is one volume
       * detected. Also, the mininum size is enforced to 0.1G.
       */
      if (is_first_volume(lc, rs))
            isw = _isw_create_first_volume(lc, rs);
      else if (rs->type == ISW_T_SPARE)
            LOG_ERR(lc, 0, "%s: SPARE disk must use all space "
                  "on the disk", handler);
      else if (is_hd_array_available(lc, rs))
            isw = _isw_create_second_volume(lc, rs);
      else
            LOG_ERR(lc, 0,
                  "%s: second volume must use all drives on the "
                  "existing array", handler);

      /* isw spare disk is created without own name. */
      if (isw) {
            static const char *fmts[] = {
                  "About to create a RAID set with the above settings. "
                        "Name <%s> will lost. Continue",
                  "About to create a RAID set with the above settings. "
                        "Continue",
            };
            const char *fmt = fmts[!(rs->type == ISW_T_SPARE && rs->name)];

            if (yes_no_prompt(lc, fmt, rs->name)) {
                  if (!update_raidset(lc, rs, isw)) {
                        dbg_free(isw);
                        LOG_ERR(lc, 0, "%s: failed to update metadata "
                              "on the raid_dev data structure ",
                              handler);
                  }
            }
            else {
                  dbg_free(isw);
                  return 0;
            }

            dbg_free(isw);
            rs->status = s_config;
            return 1;
      }

      return 0;
}

static int update_metadata(struct lib_context *lc, struct raid_set *rs);
static int
isw_create(struct lib_context *lc, struct raid_set *rs)
{

      int ret = 0;

      if (rs->status == s_init) {
            enum type raid_type;

            /*
             * The field size and type get changed
             * later to faciliate processing.
             */
            raid_type = rs->type;
            ret = _isw_create_raidset(lc, rs);
            rs->type = raid_type;
      }
      else if (rs->status == s_nosync)
            ret = update_metadata(lc, rs);

      return ret;
}

static int
isw_check(struct lib_context *lc, struct raid_set *rs)
{
      if (rs->status == s_init)
            return 1;
      else
            return T_GROUP(rs) ? _isw_check(lc, rs) : 0;
}

/*
 * IO error event handler.
 */
static int
event_io(struct lib_context *lc, struct event_io *e_io)
{
      struct raid_dev *rd = e_io->rd;
      struct isw *isw = META(rd, isw);
      struct isw_disk *disk;

      if (!(disk = get_disk(lc, rd->di, isw)))
            LOG_ERR(lc, 0, "%s: disk", handler);

      /* Avoid write trashing. */
      if (S_BROKEN(status(lc, rd)))
            return 0;

      disk->status &= ~USABLE_DISK;
      disk->status |= FAILED_DISK;

      return 1;
}

static struct event_handlers isw_event_handlers = {
      .io = event_io,
      .rd = NULL,       /* FIXME: no device add/remove event handler yet. */
};

static void
_isw_log(struct lib_context *lc, struct isw *isw)
{
      unsigned d, i, m;
      struct isw_disk *disk;
      struct isw_dev *dev;

      P("sig: \"%*s\"", isw, isw->sig, MAX_SIGNATURE_LENGTH, isw->sig);
      DP("check_sum: %u", isw, isw->check_sum);
      DP("mpb_size: %u", isw, isw->mpb_size);
      DP("family_num: %u", isw, isw->family_num);
      DP("generation_num: %u", isw, isw->generation_num);
      DP("error_log_size: %u", isw, isw->error_log_size);
      DP("attributes: %u", isw, isw->attributes);
      DP("num_disks: %u", isw, isw->num_disks);
      DP("num_raid_devs: %u", isw, isw->num_raid_devs);
      DP("error_log_pos: %u", isw, isw->error_log_pos);
      DP("cache_size: %u", isw, isw->cache_size);
      DP("orig_family_num: %u", isw, isw->orig_family_num);

      for (i = 0; i < ISW_FILLERS; i++) {
            if (isw->filler[i])
                  P("filler[%i]: %u", isw, isw->filler[i], i,
                    isw->filler[i]);
      }

      /* Disk table. */
      for (d = 0, disk = isw->disk; d < isw->num_disks; d++, disk++) {
            if (!disk->totalBlocks)
                  continue;

            P("disk[%u].serial: \"%*s\"", isw,
              disk->serial, d, MAX_RAID_SERIAL_LEN, disk->serial);
            P("disk[%u].totalBlocks: %u", isw,
              disk->totalBlocks, d, disk->totalBlocks);
            P("disk[%u].scsiId: 0x%x", isw, disk->scsiId, d, disk->scsiId);
            P("disk[%u].status: 0x%x", isw, disk->status, d, disk->status);
            P("disk[%u].owner_cfg_num: 0x%x", isw, disk->owner_cfg_num,
              d, disk->owner_cfg_num);
            for (i = 0; i < ISW_DISK_FILLERS; i++) {
                  if (disk->filler[i])
                        P("disk[%u].filler[%u]: %u", isw,
                          disk->filler[i], d, i, disk->filler[i]);
            }
      }

      /* RAID device/volume table. */
      for (d = 0; d < isw->num_raid_devs; d++) {
            dev = raiddev(isw, d);

            /* RAID device */
            P("isw_dev[%u].volume: \"%*s\"", isw,
              dev->volume, d, MAX_RAID_SERIAL_LEN, dev->volume);
            P("isw_dev[%u].SizeHigh: %u", isw, dev->SizeHigh, d,
              dev->SizeHigh);
            P("isw_dev[%u].SizeLow: %u", isw, dev->SizeLow, d,
              dev->SizeLow);
            P("isw_dev[%u].status: 0x%x", isw, dev->status, d, dev->status);
            P("isw_dev[%u].reserved_blocks: %u", isw,
              dev->reserved_blocks, d, dev->reserved_blocks);
            P("isw_dev[%u].migr_priority: %u", isw, dev->migr_priority,
              d, dev->migr_priority);
            P("isw_dev[%u].num_sub_vol: %u", isw, dev->num_sub_vol, d,
              dev->num_sub_vol);
            P("isw_dev[%u].tid: %u", isw, dev->tid, d, dev->tid);
            P("isw_dev[%u].cng_master_disk: %u", isw,
              dev->cng_master_disk, d, dev->cng_master_disk);
            P("isw_dev[%u].cache_policy: %u", isw,
              dev->cache_policy, d, dev->cache_policy);
            P("isw_dev[%u].cng_state: %u", isw, dev->cng_state, d,
              dev->cng_state);
            P("isw_dev[%u].cng_sub_state: %u", isw, dev->cng_sub_state,
              d, dev->cng_sub_state);

            for (i = 0; i < ISW_DEV_FILLERS; i++) {
                  if (dev->filler[i])
                        P("isw_dev[%u].filler[%u]: %u", isw,
                          dev->filler[i], d, i, dev->filler[i]);
            }

            /* RAID volume */
            P("isw_dev[%u].vol.curr_migr_unit: %u", isw,
              dev->vol.curr_migr_unit, d, dev->vol.curr_migr_unit);
            P("isw_dev[%u].vol.check_point_id: %u", isw,
              dev->vol.check_point_id, d, dev->vol.check_point_id);

            P("isw_dev[%u].vol.migr_state: %u", isw,
              dev->vol.migr_state, d, dev->vol.migr_state);
            P("isw_dev[%u].vol.migr_type: %u", isw,
              dev->vol.migr_type, d, dev->vol.migr_type);
            P("isw_dev[%u].vol.dirty: %u", isw, dev->vol.dirty, d,
              dev->vol.dirty);
            P("isw_dev[%u].vol.fs_state: %u", isw, dev->vol.fs_state,
              d, dev->vol.fs_state);
            P("isw_dev[%u].vol.verify_errors: %u", isw,
              dev->vol.verify_errors, d, dev->vol.verify_errors);
            P("isw_dev[%u].vol.verify_bad_blocks: %u", isw,
              dev->vol.verify_bad_blocks, d, dev->vol.verify_bad_blocks);

            for (i = 0; i < ISW_RAID_VOL_FILLERS; i++) {
                  if (dev->vol.filler[i])
                        P("isw_dev[%u].vol.filler[%u]: %u", isw,
                          dev->vol.filler[i], d, i, dev->vol.filler[i]);
            }


            struct isw_map *map = &dev->vol.map;
            for (m = 0; m < 2; m++) {
                  /* RAID map */

                  P("isw_dev[%u].vol.map[%d].pba_of_lba0: %u", isw,
                    map->pba_of_lba0, d, m, map->pba_of_lba0);
                  P("isw_dev[%u].vol.map[%d].blocks_per_member: %u",
                    isw, map->blocks_per_member, d, m,
                    map->blocks_per_member);
                  P("isw_dev[%u].vol.map[%d].num_data_stripes: %u",
                    isw, map->num_data_stripes, d, m,
                    map->num_data_stripes);
                  P("isw_dev[%u].vol.map[%d].blocks_per_strip: %u",
                    isw, map->blocks_per_strip, d, m,
                    map->blocks_per_strip);
                  P("isw_dev[%u].vol.map[%d].map_state: %u", isw,
                    map->map_state, d, m, map->map_state);
                  P("isw_dev[%u].vol.map[%d].raid_level: %u", isw,
                    map->raid_level, d, m, map->raid_level);
                  P("isw_dev[%u].vol.map[%d].num_members: %u", isw,
                    map->num_members, d, m, map->num_members);
                  P("isw_dev[%u].vol.map[%d].num_domains: %u", isw,
                    map->num_domains, d, m, map->num_domains);
                  P("isw_dev[%u].vol.map[%d].failed_disk_num: %u",
                    isw, map->failed_disk_num, d, m,
                    map->failed_disk_num);
                  P("isw_dev[%u].vol.map[%d].ddf: %u", isw, map->ddf,
                    d, m, map->ddf);

                  for (i = 0; i < 7; i++) {
                        if (map->filler[i])
                              P("isw_dev[%u].vol.map[%d].filler[%u]: %u", isw, map->filler[i], d, m, i, map->filler[i]);
                  }

                  for (i = 0; i < map->num_members; i++) {
                        P("isw_dev[%u].vol.map[%d].disk_ord_tbl[%u]: 0x%x", isw, map->disk_ord_tbl[i], d, m, i, map->disk_ord_tbl[i]);
                  }

                  if (!dev->vol.migr_state)
                        break;

                  map = (struct isw_map *) ((char *) map +
                                      (map->num_members - 1) *
                                      sizeof(map->disk_ord_tbl) +
                                      sizeof(struct isw_map));
            }
      }
}

#ifdef DMRAID_NATIVE_LOG
/*
 * Log native information about an ISW RAID device.
 */
static void
isw_log(struct lib_context *lc, struct raid_dev *rd)
{
      struct isw *isw = META(rd, isw);

      log_print(lc, "%s (%s):", rd->di->path, handler);
      _isw_log(lc, isw);
}
#endif

static void
isw_erase_metadata(struct lib_context *lc, struct raid_set *rs)
{
      struct raid_dev *rd;

      list_for_each_entry(rd, &rs->devs, devs)
            isw_write(lc, rd, 1);
}

/*
 * Write an Intel Software RAID device.
 */
static int
isw_write_all(struct lib_context *lc, struct raid_set *rs, struct isw *isw)
{
      struct raid_dev *rd, *r;
      struct meta_areas ma = {
            .size = isw_size(isw),
            .area = isw,
      };

      if (!(rd = alloc_raid_dev(lc, handler)))
            return 0;

      rd->meta_areas = &ma;
      rd->type = t_raid0;     //dummy code
      rd->areas = 1;

      list_for_each_entry(r, &rs->devs, devs) {
            rd->di = r->di;
            set_metadata_sizoff(rd, ma.size);
            rd->fmt = r->fmt;
            isw_write(lc, rd, 0);
      }

      dbg_free(rd);
      return 1;
}

/* Remove an isw device. */
static void
isw_remove_dev(struct lib_context *lc, struct raid_set *rs,
             struct isw *isw, struct isw_dev *dev)
{
      struct isw *isw_tmp;
      size_t size, dev_size;

      size = div_up(isw->mpb_size, ISW_DISK_BLOCK_SIZE);
      if (!(isw_tmp = alloc_private(lc, handler,
                              (size + 1) * ISW_DISK_BLOCK_SIZE)))
            log_err(lc, "%s: failed to allocate memory", handler);

      size = sizeof(*isw) + sizeof(struct isw_disk) * (isw->num_disks - 1);
      memcpy(isw_tmp, isw, size);

      dev_size = sizeof(*dev) +
            sizeof(uint32_t) * (dev->vol.map.num_members - 1);
      memcpy((char *) isw_tmp + size, dev, dev_size);

      /* If remaining device is a lower version, downgrade */
      if(dev->vol.map.raid_level == ISW_T_RAID1)
            strncpy((char *) isw_tmp->sig + MPB_SIGNATURE_SIZE,
                  MPB_VERSION_RAID1, MPB_VERSION_LENGTH);
      
      if((dev->vol.map.raid_level == ISW_T_RAID0) &&
                  (dev->vol.map.num_members < 3))
            strncpy((char *) isw_tmp->sig + MPB_SIGNATURE_SIZE,
                  MPB_VERSION_RAID0, MPB_VERSION_LENGTH);
      
      isw_tmp->mpb_size = size + dev_size;
      isw_tmp->num_raid_devs--;
      isw_tmp->check_sum = _checksum(isw_tmp);
      isw_write_all(lc, rs, isw_tmp);
      dbg_free(isw_tmp);
}

static int
_isw_delete_all(struct lib_context *lc, struct raid_set *rs_group)
{
      struct raid_set *rs;
      struct raid_dev *rd;
      char *name;
      struct isw *isw;
      struct isw_dev *dev1, *dev2;
      int num = 0;

      if (!(rs = list_entry(rs_group->sets.next, struct raid_set, list)))
              LOG_ERR(lc, 0, "%s: failed to find a RAID set in a group",
                    handler);

      if (!(rd = list_entry(rs_group->devs.next, struct raid_dev, devs)))
              LOG_ERR(lc, 0,
                    "%s: failed to find a raid device in RS %s",
                    handler, rs_group->name);

      if (!(isw = (struct isw *) rd->meta_areas->area))
            LOG_ERR(lc, 0, "%s: failed to locate metadata on drive %s",
                  handler, rd->di->path);

      if (isw->num_raid_devs != 2)
            LOG_ERR(lc, 0, "%s: the number of raid volumes is not 2",
                  handler);

      if ((!(dev1 = raiddev(isw, 0))) || (!(dev2 = raiddev(isw, 1))))
            LOG_ERR(lc, 0, "%s: failed to get two volume info", handler);

      list_for_each_entry(rs, &rs_group->sets, list) {
            if (!(name = get_rs_basename(rs->name)))
                  LOG_ERR(lc, 0,
                        "%s: could not find the volume to be "
                        "deleted", handler);

            if (!strcmp((const char *) dev1->volume, (const char *) name))
                  num++;

            if (!strcmp((const char *) dev2->volume, (const char *) name))
                  num++;
      }
      if (num != 2)
            LOG_ERR(lc, 0,
                  "%s: failed to find all of the RAID sets to be "
                  "deleted", handler);

      isw_erase_metadata(lc, rs_group);
      return 1;
}

/* Delete metadata according to the RAID set. */
static int
isw_delete(struct lib_context *lc, struct raid_set *rs_group)
{
      struct raid_set *rs;
      struct raid_dev *rd;
      char *name;
      struct isw *isw;
      struct isw_dev *dev1, *dev2;
      int num = 0;

      if (rs_group->type != t_group)
            LOG_ERR(lc, 0, "%s: RAID set is not a t-group type", handler);

      list_for_each_entry(rs, &rs_group->sets, list)
            num++;

      if (num > 1)
            return _isw_delete_all(lc, rs_group);

      if (!(rs = list_entry(rs_group->sets.next, struct raid_set, list)))
              LOG_ERR(lc, 0,
                    "%s: failed to find a RAID set in the group",
                    handler);

      if (!(name = get_rs_basename(rs->name)))
            LOG_ERR(lc, 0,
                  "%s: failed to find the volume to be deleted", handler);

      if (!(rd = list_entry(rs_group->devs.next, struct raid_dev, devs)))
              LOG_ERR(lc, 0,
                    "%s: failed to find a raid device in RS %s",
                    handler, rs_group->name);

      if (!(isw = (struct isw *) rd->meta_areas->area))
            LOG_ERR(lc, 0,
                  "%s: failed to locate metadata on device %s",
                  handler, rd->di->path);

      /* case if metadata on spare disk is delete */
      if (!isw->num_raid_devs && isw->num_disks == 1 &&
          (isw->disk[0].status & SPARE_DISK)) {
            isw_erase_metadata(lc, rs_group);
            return 1;
      }

      if (!(dev1 = raiddev(isw, 0)))
            LOG_ERR(lc, 0,
                  "%s: failed to find a RAID set in the group", handler);

      if (isw->num_raid_devs == 1) {
            if (!strcmp((const char *) dev1->volume, (const char *) name)) {
                  isw_erase_metadata(lc, rs_group);
                  return 1;
            }
            else
                  LOG_ERR(lc, 0, "%s: failed to find the volume %s",
                        handler, name);
      }

      if (!(dev2 = raiddev(isw, 1)))
            LOG_ERR(lc, 0,
                  "%s: failed to find a RAID set in the group", handler);

      if (!strcmp((const char *) dev1->volume, (const char *) name))
            isw_remove_dev(lc, rs_group, isw, dev2);
      else if (!strcmp((const char *) dev2->volume, (const char *) name))
            isw_remove_dev(lc, rs_group, isw, dev1);
      else
            return 0;

      return 1;
}


static struct dmraid_format isw_format = {
      .name = HANDLER,
      .descr = "Intel Software RAID",
      .caps = "0,1,01",
      .format = FMT_RAID,
      .read = isw_read,
      .write = isw_write,
      .create = isw_create,
      .delete = isw_delete,
      .group = isw_group,
      .check = isw_check,
      .metadata_handler = isw_metadata_handler,
      .events = &isw_event_handlers,
      .scope = t_scope_global /* | t_scope_local */ ,
#ifdef DMRAID_NATIVE_LOG
      .log = isw_log,
#endif
};

static struct raid_set *
change_set_name(struct lib_context *lc, struct list_head *list,
            char *o_name, char *n_name)
{
      struct raid_set *r, *ret = NULL;

      list_for_each_entry(r, list, list) {
            if (!strcmp(r->name, o_name)) {
                  ret = r;
                  r->name = n_name;
                  break;
            }
      }

      list_for_each_entry(r, list, list) {
            if ((ret = change_set_name(lc, &r->sets, o_name, n_name)))
                  r->name = n_name;
      }

      return ret;
}


/*
 * Create part of metadata (struct isw_dev) in new_isw based on
 * certain parameters.
 *
 * Note that new_isw must have its data preceedning isw_dev field already set.
 * The function returns size of created isw_dev (including map(s)).
 */
static unsigned
update_metadata_isw_dev(struct isw *new_isw,
                  int failed_disk_idx,
                  struct isw *old_isw,
                  int isw_dev_idx, unsigned isw_dev_offs)
{
      int i, map_size;
      struct isw_dev *new_dev, *old_dev = raiddev(old_isw, isw_dev_idx);

      /* Append old volume information record (the first one);
       * note that at the moment there is only one isw_map record
       * (as in the old isw_dev/isw_vol record/subrecord) and we
       * need two of them till data transfer is finished.
       */
      memcpy((void *) (new_isw->disk + new_isw->num_disks) +
             isw_dev_offs, old_dev, sizeof(struct isw_dev));

      /* Update new volume information. */
      new_dev = raiddev(new_isw, isw_dev_idx);
      new_dev->vol.migr_state = 1;  /* FIXME: replace magic numbers */
      new_dev->vol.migr_type = 1;   /* FIXME: replace magic numbers */

      /* Update information in the first map. */
      new_dev->vol.map.map_state = ISW_T_STATE_NORMAL;
      new_dev->vol.map.failed_disk_num = failed_disk_idx;

      /*
       * FIXME: disk_ord_tbl should be updated too but at the moment
       * we may leave it as it is coded below without any harm.
       */
      for (i = 0; i < new_isw->num_disks - 1; i++)
            new_dev->vol.map.disk_ord_tbl[i] = i;

      /*
       * FIXME: code commented out
       * new_isw->family_num = _checksum(new_isw) + time(NULL);
       */

      /* now let's proceed with the second, temporary map
         FIXME: we just copy the first map and update it a bit */
      map_size =
            sizeof(struct isw_map) + (new_dev->vol.map.num_members -
                                1) *
            sizeof(((struct isw_map *) NULL)->disk_ord_tbl);
      memcpy((void *) &new_dev->vol.map + map_size,
             (void *) &new_dev->vol.map, map_size);

      /*
       * FIXME: the code below should be put into
       * a new function 'raid_is_rebuildable()'.
       */
      ((struct isw_map *)
       ((void *) &new_dev->vol.map + map_size))->map_state =
            new_dev->vol.map.raid_level == ISW_T_RAID0 ?
            ISW_T_STATE_FAILED : ISW_T_STATE_DEGRADED;

      return (unsigned)
            ((unsigned long) &new_dev->vol.map + 2 * map_size) -
            ((unsigned long) new_isw->disk + new_isw->num_disks) -
            isw_dev_offs;
}

/* Update metadata wit hdrive to rebuild. */
static int
update_metadata(struct lib_context *lc, struct raid_set *rs)
{
      int failed_disk_idx = -1;     /* zero-based index of failed disk */
      int i, idx, found = 0, failed_disks_num = 0, new_isw_size, ret = 0;
      unsigned isw_dev_offs;
      const char *rebuild_set_name = lc->options[LC_REBUILD_SET].arg.str;
      struct raid_dev *rd = list_entry(rs->devs.next, struct raid_dev, devs);
      struct raid_set *sub_rs = NULL;
      struct dev_info *di = NULL;
      struct isw *isw = META(rd, isw), *new_isw = NULL;
      struct isw_disk *disk = isw->disk, *new_disk = NULL;
      struct isw_dev *new_dev = NULL;


      /*
       * Find the index of the failed disk -
       * at most we can handle 1 failed disk.
       */
      i = isw->num_disks;
      while (i--) {
            /* Check if the disk is listed. */
            list_for_each_entry(di, LC_DI(lc), list) {
                  if (!strncmp(di->serial, (const char *) disk[i].serial,
                             MAX_RAID_SERIAL_LEN))
                        goto goon;
            }

            /* Disk not found in system, i.e. it's the failed one. */
            failed_disk_idx = i;
            failed_disks_num++;

            /* Mark disk as not usable. */
            disk[i].scsiId = UNKNOWN_SCSI_ID;
            disk[i].status &= ~USABLE_DISK;
            disk[i].status |= FAILED_DISK;
            goon:
            ;
      }

      /* We must have one failed disk */
      if (failed_disks_num != 1)
            LOG_ERR(lc, 0, "%s: only one failed disk supported", handler);

      /* Now let's find the disk for rebuild. */
      if (failed_disk_idx == -1)
            /*
             * Could not find failed disk... maybe this place can
             * be used to search for and add a spare disk.
             */
            return 0;

      /* Search for a raid_dev in s_init state. */
      sub_rs = find_set(lc, NULL, rebuild_set_name, FIND_ALL);
      found = 0;
      list_for_each_entry(rd, &sub_rs->devs, devs) {
            if (rd->status == s_init) {
                  di = rd->di;
                  DM_ASSERT(di);
                  log_print(lc, "%s: drive to rebuild: %s\n",
                          handler, di->path);
                  found = 1;
                  break;
            }
      }

      /* FIXME: "TBD - remove later"  */
      if (!found && lc->options[LC_REBUILD_DISK].opt) {
            list_for_each_entry(di, LC_DI(lc), list) {
                  if (!strncmp(di->path,
                             lc->options[LC_REBUILD_DISK].arg.str,
                             strlen(di->path))) {
                        found = 1;
                        break;
                  }
            }
      }

      if (!found)       /* Error: no disk to rebuild found - exit. */
            LOG_ERR(lc, 0, "%s: no drive to rebuild", handler);

      /* Now let's start building the new metadata. */

      /* MPB can have at most two block size. */
      new_isw_size = 2 * ISW_DISK_BLOCK_SIZE;
      new_isw = alloc_private(lc, handler, new_isw_size);
      if (!new_isw)
            return 0;

      /* Copy a few first metadata bytes. */
      memcpy(new_isw, isw, sizeof(struct isw) - sizeof(struct isw_disk));

      /* some field will be updated later on; they are marked below:
       * check_sum
       * mpb_size
       family_num
       * generation_num
       error_log_size
       attributes
       * num_disks
       num_raid_devs
       error_log_pos
       cache_size
       orig_family_num
       FIXME: OROM changes some fields that are not marked above,
       so we should too
       */

      /* Add the new disk. */
      new_disk = alloc_private(lc, handler, sizeof(struct isw_disk));
      if (!new_disk)
            goto bad_free_new_isw;

      new_disk->totalBlocks = di->sectors;
      new_disk->scsiId = get_scsiId(lc, di->path);
      /* FIXME: is this state ok, Radoslaw ? Was 0x53a */
      new_disk->status = CONFIG_ON_DISK |
            DISK_SMART_EVENT_SUPPORTED |
            CLAIMED_DISK | DETECTED_DISK | USABLE_DISK | CONFIGURED_DISK;
      strncpy((char *) new_disk->serial, di->serial, MAX_RAID_SERIAL_LEN);

      /* build new isw_disk array */
      for (i = 0; i < isw->num_disks; i++) {
            /*
             * Replace failed disk with the new one or
             * Leave previous drives as they are.
             */
            memcpy(new_isw->disk + i,
                   i == failed_disk_idx ? new_disk : isw->disk + i,
                   sizeof(struct isw_disk));
      }

      /*
       * Append the failed disk at the end of the disks array in
       * the metadata; as designed in the intermediate rebuilding
       * step we have 3 disks and two maps per isw_dev: the new one
       * (at index 0) and the old one (at index 1).
       */
      memcpy(new_isw->disk + i, isw->disk + failed_disk_idx,
             sizeof(struct isw_disk));
      new_isw->disk[i].status = CONFIGURED_DISK;
      new_isw->num_disks++;

      /* Create isw_dev record for volume(s). */
      isw_dev_offs = update_metadata_isw_dev(new_isw, failed_disk_idx,
                                     isw, 0, 0);
      if (isw->num_raid_devs > 1)
            isw_dev_offs += update_metadata_isw_dev(new_isw,
                                          failed_disk_idx, isw,
                                          1, isw_dev_offs);

      /* now we may update new metadata's fields */
      new_isw->mpb_size =
            (unsigned long) (new_isw->disk + new_isw->num_disks) -
            (unsigned long) (new_isw) + isw_dev_offs;
      new_isw->generation_num++;
      new_isw->check_sum = _checksum(new_isw);

      /* embed new metadata on physical devices */
      idx = rd_idx_by_name(new_isw, rebuild_set_name + strlen(rs->name) + 1);
      if (idx < 0)
            return 0;

      new_dev = raiddev(new_isw, idx);
      sub_rs = find_set(lc, NULL, rebuild_set_name, FIND_ALL);
      list_for_each_entry(rd, &sub_rs->devs, devs) {
            if (rd->meta_areas && rd->meta_areas->area) {

                  dbg_free(rd->meta_areas->area);
            }
            if (!rd->meta_areas || rd->status == s_init) {
                  if (rd->meta_areas)
                        dbg_free(rd->meta_areas);

                  rd->meta_areas = alloc_meta_areas(lc, rd, handler, 1);
                  if (!rd->meta_areas)
                        goto bad_free_new_disk;

                  rd->di = di;
                  rd->fmt = &isw_format;
                  rd->meta_areas->area =
                        alloc_private(lc, handler, new_isw_size);
                  memcpy(rd->meta_areas->area, new_isw, new_isw_size);
                  rd->offset = new_dev->vol.map.pba_of_lba0;
                  rd->sectors = new_dev->vol.map.blocks_per_member;
            }
            else {
                  rd->meta_areas->area =
                        alloc_private(lc, handler, new_isw_size);
                  if (!rd->meta_areas->area)
                        goto bad_free_new_disk;

                  memcpy(rd->meta_areas->area, new_isw, new_isw_size);
            }

            if (!rd->areas)
                  rd->areas++;
            set_metadata_sizoff(rd, isw_size(new_isw));

            if (rd->status == s_init) {
                  rd->status = s_ok;
                  if (rd->name)
                        dbg_free(rd->name);

                  if (!(rd->name = name(lc, rd, new_dev, N_VOLUME)))
                        goto bad_free_new_disk;
            }

            rd->status = s_ok;
      }

      list_for_each_entry(rd, &rs->devs, devs) {
            if (rd->meta_areas && rd->meta_areas->area)
                  dbg_free(rd->meta_areas->area);

            if (!rd->meta_areas || rd->status == s_init) {
                  if (rd->meta_areas && rd->meta_areas->area)
                        dbg_free(rd->meta_areas->area);

                  rd->meta_areas = alloc_meta_areas(lc, rd, handler, 1);
                  if (!rd->meta_areas)
                        goto bad_free_new_disk;

                  rd->di = di;
                  rd->fmt = &isw_format;
                  rd->offset = new_dev->vol.map.pba_of_lba0;
                  rd->sectors = new_dev->vol.map.blocks_per_member;
            }
            rd->meta_areas->area = alloc_private(lc, handler, new_isw_size);
            if (!rd->meta_areas->area)
                  goto bad_free_new_disk;
            set_metadata_sizoff(rd, isw_size(new_isw));
            memcpy(rd->meta_areas->area, new_isw, new_isw_size);


            if (rd->status == s_init) {

                  if (rd->name)
                        dbg_free(rd->name);

                  if (!(rd->name = name(lc, rd, new_dev, N_VOLUME)))
                        goto bad_free_new_disk;

                  /* FIXME: code commented out
                     new_name = name(lc, rd, new_dev, 0);
                   */
            }

            rd->status = s_ok;
      }

      /* FIXME: code commented out
         change_set_name(lc, LC_RS(lc), rs->name, new_name);
       */

      ret = 1;
      bad_free_new_disk:
      dbg_free(new_disk);
      bad_free_new_isw:
      dbg_free(new_isw);
      return ret;
}

/* Register this format handler with the format core. */
int
register_isw(struct lib_context *lc)
{
      return register_format_handler(lc, &isw_format);
}

/*
 * Set the RAID device contents up derived from the Intel ones.
 *
 * This is the first one we get with here and we potentially need to
 * create many in isw_group() in case of multiple Intel SW RAID devices
 * on this RAID disk.
 */
static int
setup_rd(struct lib_context *lc, struct raid_dev *rd,
       struct dev_info *di, void *meta, union read_info *info)
{
      struct isw *isw = meta;
      struct isw_disk *disk;


      /* Superblock checksum */
      if (isw->check_sum != _checksum(isw))
            LOG_ERR(lc, 0, "%s: extended superblock for %s "
                  "has wrong checksum", handler, di->path);

      if (!(rd->meta_areas = alloc_meta_areas(lc, rd, handler, 1)))
            return 0;

      rd->meta_areas->offset = info->u64 >> 9;
      rd->meta_areas->size = isw_size(isw);
      rd->meta_areas->area = isw;

      rd->di = di;
      rd->fmt = &isw_format;

      rd->offset = ISW_DATAOFFSET;
      if (!(rd->sectors = info->u64 >> 9))
            return log_zero_sectors(lc, di->path, handler);

      rd->status = status(lc, rd);

      /* Mark disk as spare disk. */
      disk = get_disk(lc, di, isw);
      if (disk->status & SPARE_DISK)
            rd->type = t_spare;
      else
            rd->type = t_group;

      disk->scsiId = get_scsiId(lc, di->path);
      return (rd->name = name(lc, rd, NULL, N_NUMBER)) ? 1 : 0;
}