rbd_types.h

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/*
 * Ceph - scalable distributed file system
 *
 * Copyright (C) 2004-2010 Sage Weil <[email protected]>
 *
 * This is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License version 2.1, as published by the Free Software
 * Foundation.  See file COPYING.
 *
 */

#ifndef CEPH_RBD_TYPES_H
#define CEPH_RBD_TYPES_H

#include <linux/types.h>

/* For format version 2, rbd image 'foo' consists of objects
 *   rbd_id.foo     - id of image
 *   rbd_header.<id>    - image metadata
 *   rbd_data.<id>.0000000000000000
 *   rbd_data.<id>.0000000000000001
 *   ...        - data
 * Clients do not access header data directly in rbd format 2.
 */

#define RBD_HEADER_PREFIX      "rbd_header."
#define RBD_DATA_PREFIX        "rbd_data."
#define RBD_ID_PREFIX          "rbd_id."

/*
 * For format version 1, rbd image 'foo' consists of objects
 *   foo.rbd        - image metadata
 *   rb.<idhi>.<idlo>.00000000
 *   rb.<idhi>.<idlo>.00000001
 *   ...        - data
 * There is no notion of a persistent image id in rbd format 1.
 */

#define RBD_SUFFIX      ".rbd"

#define RBD_DIRECTORY           "rbd_directory"
#define RBD_INFO                "rbd_info"

#define RBD_DEFAULT_OBJ_ORDER   22   /* 4MB */
#define RBD_MIN_OBJ_ORDER       16
#define RBD_MAX_OBJ_ORDER       30

#define RBD_MAX_SEG_NAME_LEN    128

#define RBD_COMP_NONE       0
#define RBD_CRYPT_NONE      0

#define RBD_HEADER_TEXT     "<<< Rados Block Device Image >>>\n"
#define RBD_HEADER_SIGNATURE    "RBD"
#define RBD_HEADER_VERSION  "001.005"

struct rbd_image_snap_ondisk {
    __le64 id;
    __le64 image_size;
} __attribute__((packed));

struct rbd_image_header_ondisk {
    char text[40];
    char object_prefix[24];
    char signature[4];
    char version[8];
    struct {
        __u8 order;
        __u8 crypt_type;
        __u8 comp_type;
        __u8 unused;
    } __attribute__((packed)) options;
    __le64 image_size;
    __le64 snap_seq;
    __le32 snap_count;
    __le32 reserved;
    __le64 snap_names_len;
    struct rbd_image_snap_ondisk snaps[0];
} __attribute__((packed));


#endif