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_ID_PREFIX          "rbd_id."
  29#define RBD_V2_DATA_FORMAT     "%s.%016llx"
  30
  31#define RBD_LOCK_NAME          "rbd_lock"
  32#define RBD_LOCK_TAG           "internal"
  33#define RBD_LOCK_COOKIE_PREFIX "auto"
  34
  35enum rbd_notify_op {
  36        RBD_NOTIFY_OP_ACQUIRED_LOCK      = 0,
  37        RBD_NOTIFY_OP_RELEASED_LOCK      = 1,
  38        RBD_NOTIFY_OP_REQUEST_LOCK       = 2,
  39        RBD_NOTIFY_OP_HEADER_UPDATE      = 3,
  40};
  41
  42/*
  43 * For format version 1, rbd image 'foo' consists of objects
  44 *   foo.rbd            - image metadata
  45 *   rb.<idhi>.<idlo>.<extra>.000000000000
  46 *   rb.<idhi>.<idlo>.<extra>.000000000001
  47 *   ...                - data
  48 * There is no notion of a persistent image id in rbd format 1.
  49 */
  50
  51#define RBD_SUFFIX              ".rbd"
  52#define RBD_V1_DATA_FORMAT      "%s.%012llx"
  53
  54#define RBD_DIRECTORY           "rbd_directory"
  55#define RBD_INFO                "rbd_info"
  56
  57#define RBD_DEFAULT_OBJ_ORDER   22   /* 4MB */
  58#define RBD_MIN_OBJ_ORDER       16
  59#define RBD_MAX_OBJ_ORDER       30
  60
  61#define RBD_HEADER_TEXT         "<<< Rados Block Device Image >>>\n"
  62#define RBD_HEADER_SIGNATURE    "RBD"
  63#define RBD_HEADER_VERSION      "001.005"
  64
  65struct rbd_image_snap_ondisk {
  66        __le64 id;
  67        __le64 image_size;
  68} __attribute__((packed));
  69
  70struct rbd_image_header_ondisk {
  71        char text[40];
  72        char object_prefix[24];
  73        char signature[4];
  74        char version[8];
  75        struct {
  76                __u8 order;
  77                __u8 crypt_type;
  78                __u8 comp_type;
  79                __u8 unused;
  80        } __attribute__((packed)) options;
  81        __le64 image_size;
  82        __le64 snap_seq;
  83        __le32 snap_count;
  84        __le32 reserved;
  85        __le64 snap_names_len;
  86        struct rbd_image_snap_ondisk snaps[0];
  87} __attribute__((packed));
  88
  89
  90#endif
  91