LXR linux/drivers/block/rbd

   1/*
   2 * Ceph - scalable distributed file system
   3 *
   4 * Copyright (C) 2004-2010 Sage Weil <sage@newdream.net>
   5 *
   6 * This is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU Lesser General Public
   8 * License version 2.1, as published by the Free Software
   9 * Foundation.  See file COPYING.
  10 *
  11 */
  12
  13#ifndef CEPH_RBD_TYPES_H
  14#define CEPH_RBD_TYPES_H
  15
  16#include <linux/types.h>
  17
  18/* For format version 2, rbd image 'foo' consists of objects
  19 *   rbd_id.foo         - id of image
  20 *   rbd_header.<id>    - image metadata
  21 *   rbd_data.<id>.0000000000000000
  22 *   rbd_data.<id>.0000000000000001
  23 *   ...                - data
  24 * Clients do not access header data directly in rbd format 2.
  25 */
  26
  27#define RBD_HEADER_PREFIX      "rbd_header."
  28#define RBD_DATA_PREFIX        "rbd_data."
  29#define RBD_ID_PREFIX          "rbd_id."
  30
  31/*
  32 * For format version 1, rbd image 'foo' consists of objects
  33 *   foo.rbd            - image metadata
  34 *   rb.<idhi>.<idlo>.00000000
  35 *   rb.<idhi>.<idlo>.00000001
  36 *   ...                - data
  37 * There is no notion of a persistent image id in rbd format 1.
  38 */
  39
  40#define RBD_SUFFIX              ".rbd"
  41
  42#define RBD_DIRECTORY           "rbd_directory"
  43#define RBD_INFO                "rbd_info"
  44
  45#define RBD_DEFAULT_OBJ_ORDER   22   /* 4MB */
  46#define RBD_MIN_OBJ_ORDER       16
  47#define RBD_MAX_OBJ_ORDER       30
  48
  49#define RBD_COMP_NONE           0
  50#define RBD_CRYPT_NONE          0
  51
  52#define RBD_HEADER_TEXT         "<<< Rados Block Device Image >>>\n"
  53#define RBD_HEADER_SIGNATURE    "RBD"
  54#define RBD_HEADER_VERSION      "001.005"
  55
  56struct rbd_image_snap_ondisk {
  57        __le64 id;
  58        __le64 image_size;
  59} __attribute__((packed));
  60
  61struct rbd_image_header_ondisk {
  62        char text[40];
  63        char object_prefix[24];
  64        char signature[4];
  65        char version[8];
  66        struct {
  67                __u8 order;
  68                __u8 crypt_type;
  69                __u8 comp_type;
  70                __u8 unused;
  71        } __attribute__((packed)) options;
  72        __le64 image_size;
  73        __le64 snap_seq;
  74        __le32 snap_count;
  75        __le32 reserved;
  76        __le64 snap_names_len;
  77        struct rbd_image_snap_ondisk snaps[0];
  78} __attribute__((packed));
  79
  80
  81#endif
  82