ceph/src/include/rbd_types.h

   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 "include/types.h"
  17 #include "rbd/features.h"
  18
  19 /* New-style rbd image 'foo' consists of objects
  20  *   rbd_id.foo              - id of image
  21  *   rbd_header.<id>         - image metadata
  22  *   rbd_object_map.<id>     - optional image object map
  23  *   rbd_data.<id>.00000000
  24  *   rbd_data.<id>.00000001
  25  *   ...                     - data
  26  */
  27
  28 #define RBD_HEADER_PREFIX      "rbd_header."
  29 #define RBD_OBJECT_MAP_PREFIX  "rbd_object_map."
  30 #define RBD_DATA_PREFIX        "rbd_data."
  31 #define RBD_ID_PREFIX          "rbd_id."
  32
  33 /*
  34  * old-style rbd image 'foo' consists of objects
  35  *   foo.rbd      - image metadata
  36  *   rb.<idhi>.<idlo>.00000000
  37  *   rb.<idhi>.<idlo>.00000001
  38  *   ...          - data
  39  */
  40
  41 #define RBD_SUFFIX              ".rbd"
  42 #define RBD_DIRECTORY           "rbd_directory"
  43 #define RBD_INFO                "rbd_info"
  44 #define RBD_NAMESPACE           "rbd_namespace"
  45 #define RBD_TASK                "rbd_task"
  46
  47 /*
  48  * rbd_children object in each pool contains omap entries
  49  * that map parent (poolid, imageid, snapid) to a list of children
  50  * (imageids; snapids aren't required because we get all the snapshot
  51  * info from a read of the child's header object anyway).
  52  *
  53  * The clone operation writes a new item to this child list, and rm or
  54  * flatten removes an item, and may remove the whole entry if no children
  55  * exist after the rm/flatten.
  56  *
  57  * When attempting to remove a parent, all pools are searched for
  58  * rbd_children objects with entries referring to that parent; if any
  59  * exist (and those children exist), the parent removal is prevented.
  60  */
  61 #define RBD_CHILDREN            "rbd_children"
  62 #define RBD_LOCK_NAME           "rbd_lock"
  63
  64 /**
  65  * rbd_mirroring object in each pool contains pool-specific settings
  66  * for configuring mirroring.
  67  */
  68 #define RBD_MIRRORING       "rbd_mirroring"
  69
  70 /**
  71  * rbd_mirror_leader and rbd_mirror_instance.<instance id> objects are used
  72  * for pool-level coordination between rbd-mirror daemons.
  73  */
  74 #define RBD_MIRROR_LEADER               "rbd_mirror_leader"
  75 #define RBD_MIRROR_INSTANCE_PREFIX      "rbd_mirror_instance."
  76
  77 #define RBD_MAX_OBJ_NAME_SIZE   96
  78 #define RBD_MAX_BLOCK_NAME_SIZE 24
  79
  80 /**
  81  * Maximum string length of the RBD v2 image id (not including
  82  * null termination). This limit was derived from the existing
  83  * RBD_MAX_BLOCK_NAME_SIZE limit which needs to hold the "rbd_data."
  84  * prefix and null termination.
  85  */
  86 #define RBD_MAX_IMAGE_ID_LENGTH 14
  87
  88 /**
  89  * Maximum string length of the RBD block object name prefix (not including
  90  * null termination).
  91  *
  92  * v1 format: rb.<max 8-byte high id>.<max 8-byte low id>.<max 8-byte extra>
  93  * v2 format: rbd_data.[<max 19-byte pool id>.]<max 14-byte image id>
  94  *
  95  * Note: new features might require increasing this maximum prefix length.
  96  */
  97 #define RBD_MAX_BLOCK_NAME_PREFIX_LENGTH 43
  98
  99 #define RBD_COMP_NONE           0
 100 #define RBD_CRYPT_NONE          0
 101
 102 #define RBD_HEADER_TEXT         "<<< Rados Block Device Image >>>\n"
 103 #define RBD_MIGRATE_HEADER_TEXT "<<< Migrating RBD Image      >>>\n"
 104 #define RBD_HEADER_SIGNATURE    "RBD"
 105 #define RBD_HEADER_VERSION      "001.005"
 106
 107 #define RBD_GROUP_INVALID_POOL (-1)
 108
 109 #define RBD_GROUP_HEADER_PREFIX "rbd_group_header."
 110
 111 #define RBD_GROUP_DIRECTORY "rbd_group_directory"
 112
 113 #define RBD_TRASH "rbd_trash"
 114
 115 /**
 116  * MON config-key prefix for storing optional remote cluster connectivity
 117  * parameters
 118  */
 119 #define RBD_MIRROR_PEER_CONFIG_KEY_PREFIX "rbd/mirror/peer/"
 120
 121 struct rbd_info {
 122         __le64 max_id;
 123 } __attribute__ ((packed));
 124
 125 struct rbd_obj_snap_ondisk {
 126         __le64 id;
 127         __le64 image_size;
 128 } __attribute__((packed));
 129
 130 struct rbd_obj_header_ondisk {
 131         char text[40];
 132         char block_name[RBD_MAX_BLOCK_NAME_SIZE];
 133         char signature[4];
 134         char version[8];
 135         struct {
 136                 __u8 order;
 137                 __u8 crypt_type;
 138                 __u8 comp_type;
 139                 __u8 unused;
 140         } __attribute__((packed)) options;
 141         __le64 image_size;
 142         __le64 snap_seq;
 143         __le32 snap_count;
 144         __le32 reserved;
 145         __le64 snap_names_len;
 146         struct rbd_obj_snap_ondisk snaps[0];
 147 } __attribute__((packed));
 148
 149 enum {
 150   RBD_PROTECTION_STATUS_UNPROTECTED  = 0,
 151   RBD_PROTECTION_STATUS_UNPROTECTING = 1,
 152   RBD_PROTECTION_STATUS_PROTECTED    = 2,
 153   RBD_PROTECTION_STATUS_LAST         = 3
 154 };
 155
 156 #endif