/*      $NetBSD: efs_dinode.h,v 1.3 2016/07/07 06:55:42 msaitoh Exp $   */

/*
 * Copyright (c) 2006 Stephen M. Rumble <rumble@ephemeral.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * EFS on-disk inode format.
 *
 * See IRIX inode(4)
 */

#ifndef _FS_EFS_EFS_DINODE_H_
#define _FS_EFS_EFS_DINODE_H_

/*
 * Historical locations are always good.
 */
#define EFS_ROOTINO     ((ino_t)2)

/*
 * EFS on-disk inode structure (128 bytes)
 *
 * [0] - NetBSD native uid_t is uint32_t.
 * [1] - NetBSD native gid_t is uint32_t.
 * [2] - NetBSD native off_t is int64_t.
 * [3] - See notes for di_u below for meanings of di_numextents.
 * [4] - Always 0 with EFS. Apparently it could take on other values when
 *       used in conjunction with AFS.
 */

#define EFS_DIRECTEXTENTS 12
struct efs_dinode {
        uint16_t        di_mode;        /* 0:  file type and permissions */
        int16_t         di_nlink;       /* 2:  link count (minimum 2) */
        uint16_t        di_uid;         /* 4:  user ID [0] */
        uint16_t        di_gid;         /* 6:  group ID [1] */
        int32_t         di_size;        /* 8:  file size (in bytes) [2] */
        uint32_t        di_atime;       /* 12: file access time */
        uint32_t        di_mtime;       /* 16: file modification time */
        uint32_t        di_ctime;       /* 20: inode modification time */
        int32_t         di_gen;         /* 24: inode generation number */
        int16_t         di_numextents;  /* 28: number of extents in file [3] */
        uint8_t         di_version;     /* 30: inode version [4] */
        uint8_t         di_spare;       /* 31: unused */

        union {
                /*
                 * If di_numextents <= EFS_DIRECTEXTENTS, _di_extents contains
                 * direct extent descriptors. 
                 *
                 * else (di_numextents > EFS_DIRECTEXTENTS), _di_extents
                 * contains indirect extent descriptors.
                 *
                 * If indirect extents are being used, extents[0].ex_offset
                 * contains the number of indirect extents, i.e. the valid
                 * offsets in 'extents' are:
                 *     extents[0 ... (extents[0].ex_offset - 1)]
                 * It's not presently known if the ex_offset fields in
                 * extents[1 ... EFS_DIRECTEXTENTS] have any meaning.
                 */
                struct efs_dextent extents[EFS_DIRECTEXTENTS];

                /*
                 * If di_numextents == 0 and di_mode indicates a symlink, the
                 * symlink path is inlined into _di_symlink. Otherwise, the
                 * symlink exists in extents.
                 *
                 * Note that the symlink is stored without nul-termination,
                 * and di_size reflects this length.
                 */
                char symlink[sizeof(struct efs_dextent) * EFS_DIRECTEXTENTS];

                /*
                 * If di_numextents == 0 and di_mode indicates a character or
                 * block special file, the device tag is contained in _di_dev. 
                 *
                 * Note that IRIX moved from 16bit to 32bit dev_t's at some 
                 * point and a new field was added. It appears that when 32bit
                 * dev_t's are used, di_odev is set to 0xffff.
                 */
                struct {
                        uint16_t dev_old;
                        uint32_t dev_new;
                } __packed dev;
        } di_u;
} __packed;

#define di_extents      di_u.extents
#define di_symlink      di_u.symlink
#define di_odev         di_u.dev.dev_old
#define di_ndev         di_u.dev.dev_new

#define EFS_DINODE_SIZE         sizeof(struct efs_dinode)
#define EFS_DINODES_PER_BB      (EFS_BB_SIZE / EFS_DINODE_SIZE)

#define EFS_DINODE_ODEV_INVALID (0xffff)
#define EFS_DINODE_ODEV_MAJ(_x) (((_x) >>  8) & 0x7f)
#define EFS_DINODE_ODEV_MIN(_x) (((_x) >>  0) & 0xff)
#define EFS_DINODE_NDEV_MAJ(_x) (((_x) >> 18) & 0x1ff)
#define EFS_DINODE_NDEV_MIN(_x) (((_x) >>  0) & 0x3ffff)

/* EFS file permissions. */
#define EFS_IEXEC       0000100         /* executable */
#define EFS_IWRITE      0000200         /* writable */
#define EFS_IREAD       0000400         /* readable */
#define EFS_ISVTX       0001000         /* sticky bit */
#define EFS_ISGID       0002000         /* setgid */
#define EFS_ISUID       0004000         /* setuid */

/* EFS file types. */
#define EFS_IFMT        0170000         /* file type mask */
#define EFS_IFIFO       0010000         /* named pipe */
#define EFS_IFCHR       0020000         /* character device */
#define EFS_IFDIR       0040000         /* directory */
#define EFS_IFBLK       0060000         /* block device */
#define EFS_IFREG       0100000         /* regular file */
#define EFS_IFLNK       0120000         /* symlink */
#define EFS_IFSOCK      0140000         /* UNIX domain socket */

#endif /* !_FS_EFS_EFS_DINODE_H_ */