/*

 * Evms topology

 * -- this is fallback for old systems where the topology information is not

 *    exported by sysfs

 *

 * Copyright (C) 2009 Karel Zak <kzak@redhat.com>

 *

 * This file may be redistributed under the terms of the

 * GNU Lesser General Public License.

 *

 */

#include <errno.h>

#include <fcntl.h>

#include <stdint.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sys/ioctl.h>

#include <sys/stat.h>

#include <sys/types.h>

#include <unistd.h>

#include "topology.h"

#define EVMS_MAJOR    117

#ifndef _IOT__IOTBASE_u_int32_t

#define _IOT__IOTBASE_u_int32_t IOT_SIMPLE(uint32_t)

#endif

#define _IOT_evms_stripe_info _IOT (_IOTS(uint32_t), 2, 0, 0, 0, 0)

#define EVMS_GET_STRIPE_INFO  _IOR(EVMS_MAJOR, 0xF0, struct evms_stripe_info)

struct evms_stripe_info {

  uint32_t  size;   /* stripe unit 512-byte blocks */

  uint32_t  width;    /* the number of stripe members or RAID data disks */

};

static int is_evms_device(dev_t devno)

{

  if (major(devno) == EVMS_MAJOR)

    return 1;

  return blkid_driver_has_major("evms", major(devno));

}

static int probe_evms_tp(blkid_probe pr,

    const struct blkid_idmag *mag __attribute__((__unused__)))

{

  struct evms_stripe_info evms;

  dev_t devno = blkid_probe_get_devno(pr);

  if (!devno)

    goto nothing;   /* probably not a block device */

  if (!is_evms_device(devno))

    goto nothing;

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

  if (ioctl(pr->fd, EVMS_GET_STRIPE_INFO, &evms))

    goto nothing;

  blkid_topology_set_minimum_io_size(pr, evms.size << 9);

  blkid_topology_set_optimal_io_size(pr, (evms.size * evms.width) << 9);

  return 0;

nothing:

  return 1;

}

const struct blkid_idinfo evms_tp_idinfo =

{

  .name   = "evms",

  .probefunc  = probe_evms_tp,

  .magics   = BLKID_NONE_MAGIC

};