aboutsummaryrefslogtreecommitdiffstats
path: root/fs/exofs/common.h
blob: b1b178e61718a5a7cee88ee7e2083b9fa5f3a3bd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
/*
 * 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 <bharrosh@panasas.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 */
# define EXOFS_APAGE_FS_DATA	(OSD_APAGE_APP_DEFINED_FIRST + 3)
# define EXOFS_ATTR_INODE_DATA	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;	/* Highest object ID used */
	__le64  s_numfiles;	/* Number of files on fs */
	__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;

/*
 * 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 begining. 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, Ususally 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)

#endif /*ifndef __EXOFS_COM_H__*/