linux/fs/exofs/common.h

263 lines
8.6 KiB
C

/*
* common.h - Common definitions for both Kernel and user-mode utilities
*
* Copyright (C) 2005, 2006
* Avishay Traeger (avishay@gmail.com)
* Copyright (C) 2008, 2009
* Boaz Harrosh <ooo@electrozaur.com>
*
* Copyrights for code taken from ext2:
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
* from
* linux/fs/minix/inode.c
* Copyright (C) 1991, 1992 Linus Torvalds
*
* This file is part of exofs.
*
* exofs is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation. Since it is based on ext2, and the only
* valid version of GPL for the Linux kernel is version 2, the only valid
* version of GPL for exofs is version 2.
*
* exofs is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with exofs; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __EXOFS_COM_H__
#define __EXOFS_COM_H__
#include <linux/types.h>
#include <scsi/osd_attributes.h>
#include <scsi/osd_initiator.h>
#include <scsi/osd_sec.h>
/****************************************************************************
* Object ID related defines
* NOTE: inode# = object ID - EXOFS_OBJ_OFF
****************************************************************************/
#define EXOFS_MIN_PID 0x10000 /* Smallest partition ID */
#define EXOFS_OBJ_OFF 0x10000 /* offset for objects */
#define EXOFS_SUPER_ID 0x10000 /* object ID for on-disk superblock */
#define EXOFS_DEVTABLE_ID 0x10001 /* object ID for on-disk device table */
#define EXOFS_ROOT_ID 0x10002 /* object ID for root directory */
/* exofs Application specific page/attribute */
/* Inode attrs */
# define EXOFS_APAGE_FS_DATA (OSD_APAGE_APP_DEFINED_FIRST + 3)
# define EXOFS_ATTR_INODE_DATA 1
# define EXOFS_ATTR_INODE_FILE_LAYOUT 2
# define EXOFS_ATTR_INODE_DIR_LAYOUT 3
/* Partition attrs */
# define EXOFS_APAGE_SB_DATA (0xF0000000U + 3)
# define EXOFS_ATTR_SB_STATS 1
/*
* The maximum number of files we can have is limited by the size of the
* inode number. This is the largest object ID that the file system supports.
* Object IDs 0, 1, and 2 are always in use (see above defines).
*/
enum {
EXOFS_MAX_INO_ID = (sizeof(ino_t) * 8 == 64) ? ULLONG_MAX :
(1ULL << (sizeof(ino_t) * 8ULL - 1ULL)),
EXOFS_MAX_ID = (EXOFS_MAX_INO_ID - 1 - EXOFS_OBJ_OFF),
};
/****************************************************************************
* Misc.
****************************************************************************/
#define EXOFS_BLKSHIFT 12
#define EXOFS_BLKSIZE (1UL << EXOFS_BLKSHIFT)
/****************************************************************************
* superblock-related things
****************************************************************************/
#define EXOFS_SUPER_MAGIC 0x5DF5
/*
* The file system control block - stored in object EXOFS_SUPER_ID's data.
* This is where the in-memory superblock is stored on disk.
*/
enum {EXOFS_FSCB_VER = 1, EXOFS_DT_VER = 1};
struct exofs_fscb {
__le64 s_nextid; /* Only used after mkfs */
__le64 s_numfiles; /* Only used after mkfs */
__le32 s_version; /* == EXOFS_FSCB_VER */
__le16 s_magic; /* Magic signature */
__le16 s_newfs; /* Non-zero if this is a new fs */
/* From here on it's a static part, only written by mkexofs */
__le64 s_dev_table_oid; /* Resurved, not used */
__le64 s_dev_table_count; /* == 0 means no dev_table */
} __packed;
/*
* This struct is set on the FS partition's attributes.
* [EXOFS_APAGE_SB_DATA, EXOFS_ATTR_SB_STATS] and is written together
* with the create command, to atomically persist the sb writeable information.
*/
struct exofs_sb_stats {
__le64 s_nextid; /* Highest object ID used */
__le64 s_numfiles; /* Number of files on fs */
} __packed;
/*
* Describes the raid used in the FS. It is part of the device table.
* This here is taken from the pNFS-objects definition. In exofs we
* use one raid policy through-out the filesystem. (NOTE: the funny
* alignment at beginning. We take care of it at exofs_device_table.
*/
struct exofs_dt_data_map {
__le32 cb_num_comps;
__le64 cb_stripe_unit;
__le32 cb_group_width;
__le32 cb_group_depth;
__le32 cb_mirror_cnt;
__le32 cb_raid_algorithm;
} __packed;
/*
* This is an osd device information descriptor. It is a single entry in
* the exofs device table. It describes an osd target lun which
* contains data belonging to this FS. (Same partition_id on all devices)
*/
struct exofs_dt_device_info {
__le32 systemid_len;
u8 systemid[OSD_SYSTEMID_LEN];
__le64 long_name_offset; /* If !0 then offset-in-file */
__le32 osdname_len; /* */
u8 osdname[44]; /* Embbeded, Usually an asci uuid */
} __packed;
/*
* The EXOFS device table - stored in object EXOFS_DEVTABLE_ID's data.
* It contains the raid used for this multy-device FS and an array of
* participating devices.
*/
struct exofs_device_table {
__le32 dt_version; /* == EXOFS_DT_VER */
struct exofs_dt_data_map dt_data_map; /* Raid policy to use */
/* Resurved space For future use. Total includeing this:
* (8 * sizeof(le64))
*/
__le64 __Resurved[4];
__le64 dt_num_devices; /* Array size */
struct exofs_dt_device_info dt_dev_table[]; /* Array of devices */
} __packed;
/****************************************************************************
* inode-related things
****************************************************************************/
#define EXOFS_IDATA 5
/*
* The file control block - stored in an object's attributes. This is where
* the in-memory inode is stored on disk.
*/
struct exofs_fcb {
__le64 i_size; /* Size of the file */
__le16 i_mode; /* File mode */
__le16 i_links_count; /* Links count */
__le32 i_uid; /* Owner Uid */
__le32 i_gid; /* Group Id */
__le32 i_atime; /* Access time */
__le32 i_ctime; /* Creation time */
__le32 i_mtime; /* Modification time */
__le32 i_flags; /* File flags (unused for now)*/
__le32 i_generation; /* File version (for NFS) */
__le32 i_data[EXOFS_IDATA]; /* Short symlink names and device #s */
};
#define EXOFS_INO_ATTR_SIZE sizeof(struct exofs_fcb)
/* This is the Attribute the fcb is stored in */
static const struct __weak osd_attr g_attr_inode_data = ATTR_DEF(
EXOFS_APAGE_FS_DATA,
EXOFS_ATTR_INODE_DATA,
EXOFS_INO_ATTR_SIZE);
/****************************************************************************
* dentry-related things
****************************************************************************/
#define EXOFS_NAME_LEN 255
/*
* The on-disk directory entry
*/
struct exofs_dir_entry {
__le64 inode_no; /* inode number */
__le16 rec_len; /* directory entry length */
u8 name_len; /* name length */
u8 file_type; /* umm...file type */
char name[EXOFS_NAME_LEN]; /* file name */
};
enum {
EXOFS_FT_UNKNOWN,
EXOFS_FT_REG_FILE,
EXOFS_FT_DIR,
EXOFS_FT_CHRDEV,
EXOFS_FT_BLKDEV,
EXOFS_FT_FIFO,
EXOFS_FT_SOCK,
EXOFS_FT_SYMLINK,
EXOFS_FT_MAX
};
#define EXOFS_DIR_PAD 4
#define EXOFS_DIR_ROUND (EXOFS_DIR_PAD - 1)
#define EXOFS_DIR_REC_LEN(name_len) \
(((name_len) + offsetof(struct exofs_dir_entry, name) + \
EXOFS_DIR_ROUND) & ~EXOFS_DIR_ROUND)
/*
* The on-disk (optional) layout structure.
* sits in an EXOFS_ATTR_INODE_FILE_LAYOUT or EXOFS_ATTR_INODE_DIR_LAYOUT
* attribute, attached to any inode, usually to a directory.
*/
enum exofs_inode_layout_gen_functions {
LAYOUT_MOVING_WINDOW = 0,
LAYOUT_IMPLICT = 1,
};
struct exofs_on_disk_inode_layout {
__le16 gen_func; /* One of enum exofs_inode_layout_gen_functions */
__le16 pad;
union {
/* gen_func == LAYOUT_MOVING_WINDOW (default) */
struct exofs_layout_sliding_window {
__le32 num_devices; /* first n devices in global-table*/
} sliding_window __packed;
/* gen_func == LAYOUT_IMPLICT */
struct exofs_layout_implict_list {
struct exofs_dt_data_map data_map;
/* Variable array of size data_map.cb_num_comps. These
* are device indexes of the devices in the global table
*/
__le32 dev_indexes[];
} implict __packed;
};
} __packed;
static inline size_t exofs_on_disk_inode_layout_size(unsigned max_devs)
{
return sizeof(struct exofs_on_disk_inode_layout) +
max_devs * sizeof(__le32);
}
#endif /*ifndef __EXOFS_COM_H__*/