xfs_dinode.h

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/*
 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program 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.
 *
 * This program is distributed in the hope that it would 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 this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#ifndef __XFS_DINODE_H__
#define __XFS_DINODE_H__

#define XFS_DINODE_MAGIC        0x494e  /* 'IN' */
#define XFS_DINODE_GOOD_VERSION(v)  (((v) == 1 || (v) == 2))

typedef struct xfs_timestamp {
    __be32      t_sec;      /* timestamp seconds */
    __be32      t_nsec;     /* timestamp nanoseconds */
} xfs_timestamp_t;

/*
 * On-disk inode structure.
 *
 * This is just the header or "dinode core", the inode is expanded to fill a
 * variable size the leftover area split into a data and an attribute fork.
 * The format of the data and attribute fork depends on the format of the
 * inode as indicated by di_format and di_aformat.  To access the data and
 * attribute use the XFS_DFORK_DPTR, XFS_DFORK_APTR, and XFS_DFORK_PTR macros
 * below.
 *
 * There is a very similar struct icdinode in xfs_inode which matches the
 * layout of the first 96 bytes of this structure, but is kept in native
 * format instead of big endian.
 */
typedef struct xfs_dinode {
    __be16      di_magic;   /* inode magic # = XFS_DINODE_MAGIC */
    __be16      di_mode;    /* mode and type of file */
    __u8        di_version; /* inode version */
    __u8        di_format;  /* format of di_c data */
    __be16      di_onlink;  /* old number of links to file */
    __be32      di_uid;     /* owner's user id */
    __be32      di_gid;     /* owner's group id */
    __be32      di_nlink;   /* number of links to file */
    __be16      di_projid_lo;   /* lower part of owner's project id */
    __be16      di_projid_hi;   /* higher part owner's project id */
    __u8        di_pad[6];  /* unused, zeroed space */
    __be16      di_flushiter;   /* incremented on flush */
    xfs_timestamp_t di_atime;   /* time last accessed */
    xfs_timestamp_t di_mtime;   /* time last modified */
    xfs_timestamp_t di_ctime;   /* time created/inode modified */
    __be64      di_size;    /* number of bytes in file */
    __be64      di_nblocks; /* # of direct & btree blocks used */
    __be32      di_extsize; /* basic/minimum extent size for file */
    __be32      di_nextents;    /* number of extents in data fork */
    __be16      di_anextents;   /* number of extents in attribute fork*/
    __u8        di_forkoff; /* attr fork offs, <<3 for 64b align */
    __s8        di_aformat; /* format of attr fork's data */
    __be32      di_dmevmask;    /* DMIG event mask */
    __be16      di_dmstate; /* DMIG state info */
    __be16      di_flags;   /* random flags, XFS_DIFLAG_... */
    __be32      di_gen;     /* generation number */

    /* di_next_unlinked is the only non-core field in the old dinode */
    __be32      di_next_unlinked;/* agi unlinked list ptr */
} __attribute__((packed)) xfs_dinode_t;

#define DI_MAX_FLUSH 0xffff

/*
 * The 32 bit link count in the inode theoretically maxes out at UINT_MAX.
 * Since the pathconf interface is signed, we use 2^31 - 1 instead.
 * The old inode format had a 16 bit link count, so its maximum is USHRT_MAX.
 */
#define XFS_MAXLINK     ((1U << 31) - 1U)
#define XFS_MAXLINK_1       65535U

/*
 * Values for di_format
 */
typedef enum xfs_dinode_fmt {
    XFS_DINODE_FMT_DEV,     /* xfs_dev_t */
    XFS_DINODE_FMT_LOCAL,       /* bulk data */
    XFS_DINODE_FMT_EXTENTS,     /* struct xfs_bmbt_rec */
    XFS_DINODE_FMT_BTREE,       /* struct xfs_bmdr_block */
    XFS_DINODE_FMT_UUID     /* uuid_t */
} xfs_dinode_fmt_t;

/*
 * Inode minimum and maximum sizes.
 */
#define XFS_DINODE_MIN_LOG  8
#define XFS_DINODE_MAX_LOG  11
#define XFS_DINODE_MIN_SIZE (1 << XFS_DINODE_MIN_LOG)
#define XFS_DINODE_MAX_SIZE (1 << XFS_DINODE_MAX_LOG)

/*
 * Inode size for given fs.
 */
#define XFS_LITINO(mp) \
    ((int)(((mp)->m_sb.sb_inodesize) - sizeof(struct xfs_dinode)))

#define XFS_BROOT_SIZE_ADJ  \
    (XFS_BTREE_LBLOCK_LEN - sizeof(xfs_bmdr_block_t))

/*
 * Inode data & attribute fork sizes, per inode.
 */
#define XFS_DFORK_Q(dip)        ((dip)->di_forkoff != 0)
#define XFS_DFORK_BOFF(dip)     ((int)((dip)->di_forkoff << 3))

#define XFS_DFORK_DSIZE(dip,mp) \
    (XFS_DFORK_Q(dip) ? \
        XFS_DFORK_BOFF(dip) : \
        XFS_LITINO(mp))
#define XFS_DFORK_ASIZE(dip,mp) \
    (XFS_DFORK_Q(dip) ? \
        XFS_LITINO(mp) - XFS_DFORK_BOFF(dip) : \
        0)
#define XFS_DFORK_SIZE(dip,mp,w) \
    ((w) == XFS_DATA_FORK ? \
        XFS_DFORK_DSIZE(dip, mp) : \
        XFS_DFORK_ASIZE(dip, mp))

/*
 * Return pointers to the data or attribute forks.
 */
#define XFS_DFORK_DPTR(dip) \
    ((char *)(dip) + sizeof(struct xfs_dinode))
#define XFS_DFORK_APTR(dip) \
    (XFS_DFORK_DPTR(dip) + XFS_DFORK_BOFF(dip))
#define XFS_DFORK_PTR(dip,w)    \
    ((w) == XFS_DATA_FORK ? XFS_DFORK_DPTR(dip) : XFS_DFORK_APTR(dip))

#define XFS_DFORK_FORMAT(dip,w) \
    ((w) == XFS_DATA_FORK ? \
        (dip)->di_format : \
        (dip)->di_aformat)
#define XFS_DFORK_NEXTENTS(dip,w) \
    ((w) == XFS_DATA_FORK ? \
        be32_to_cpu((dip)->di_nextents) : \
        be16_to_cpu((dip)->di_anextents))

#define XFS_BUF_TO_DINODE(bp)   ((xfs_dinode_t *)((bp)->b_addr))

/*
 * For block and character special files the 32bit dev_t is stored at the
 * beginning of the data fork.
 */
static inline xfs_dev_t xfs_dinode_get_rdev(struct xfs_dinode *dip)
{
    return be32_to_cpu(*(__be32 *)XFS_DFORK_DPTR(dip));
}

static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
{
    *(__be32 *)XFS_DFORK_DPTR(dip) = cpu_to_be32(rdev);
}

/*
 * Values for di_flags
 * There should be a one-to-one correspondence between these flags and the
 * XFS_XFLAG_s.
 */
#define XFS_DIFLAG_REALTIME_BIT  0  /* file's blocks come from rt area */
#define XFS_DIFLAG_PREALLOC_BIT  1  /* file space has been preallocated */
#define XFS_DIFLAG_NEWRTBM_BIT   2  /* for rtbitmap inode, new format */
#define XFS_DIFLAG_IMMUTABLE_BIT 3  /* inode is immutable */
#define XFS_DIFLAG_APPEND_BIT    4  /* inode is append-only */
#define XFS_DIFLAG_SYNC_BIT      5  /* inode is written synchronously */
#define XFS_DIFLAG_NOATIME_BIT   6  /* do not update atime */
#define XFS_DIFLAG_NODUMP_BIT    7  /* do not dump */
#define XFS_DIFLAG_RTINHERIT_BIT 8  /* create with realtime bit set */
#define XFS_DIFLAG_PROJINHERIT_BIT   9  /* create with parents projid */
#define XFS_DIFLAG_NOSYMLINKS_BIT   10  /* disallow symlink creation */
#define XFS_DIFLAG_EXTSIZE_BIT      11  /* inode extent size allocator hint */
#define XFS_DIFLAG_EXTSZINHERIT_BIT 12  /* inherit inode extent size */
#define XFS_DIFLAG_NODEFRAG_BIT     13  /* do not reorganize/defragment */
#define XFS_DIFLAG_FILESTREAM_BIT   14  /* use filestream allocator */
#define XFS_DIFLAG_REALTIME      (1 << XFS_DIFLAG_REALTIME_BIT)
#define XFS_DIFLAG_PREALLOC      (1 << XFS_DIFLAG_PREALLOC_BIT)
#define XFS_DIFLAG_NEWRTBM       (1 << XFS_DIFLAG_NEWRTBM_BIT)
#define XFS_DIFLAG_IMMUTABLE     (1 << XFS_DIFLAG_IMMUTABLE_BIT)
#define XFS_DIFLAG_APPEND        (1 << XFS_DIFLAG_APPEND_BIT)
#define XFS_DIFLAG_SYNC          (1 << XFS_DIFLAG_SYNC_BIT)
#define XFS_DIFLAG_NOATIME       (1 << XFS_DIFLAG_NOATIME_BIT)
#define XFS_DIFLAG_NODUMP        (1 << XFS_DIFLAG_NODUMP_BIT)
#define XFS_DIFLAG_RTINHERIT     (1 << XFS_DIFLAG_RTINHERIT_BIT)
#define XFS_DIFLAG_PROJINHERIT   (1 << XFS_DIFLAG_PROJINHERIT_BIT)
#define XFS_DIFLAG_NOSYMLINKS    (1 << XFS_DIFLAG_NOSYMLINKS_BIT)
#define XFS_DIFLAG_EXTSIZE       (1 << XFS_DIFLAG_EXTSIZE_BIT)
#define XFS_DIFLAG_EXTSZINHERIT  (1 << XFS_DIFLAG_EXTSZINHERIT_BIT)
#define XFS_DIFLAG_NODEFRAG      (1 << XFS_DIFLAG_NODEFRAG_BIT)
#define XFS_DIFLAG_FILESTREAM    (1 << XFS_DIFLAG_FILESTREAM_BIT)

#ifdef CONFIG_XFS_RT
#define XFS_IS_REALTIME_INODE(ip) ((ip)->i_d.di_flags & XFS_DIFLAG_REALTIME)
#else
#define XFS_IS_REALTIME_INODE(ip) (0)
#endif

#define XFS_DIFLAG_ANY \
    (XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \
     XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \
     XFS_DIFLAG_NOATIME | XFS_DIFLAG_NODUMP | XFS_DIFLAG_RTINHERIT | \
     XFS_DIFLAG_PROJINHERIT | XFS_DIFLAG_NOSYMLINKS | XFS_DIFLAG_EXTSIZE | \
     XFS_DIFLAG_EXTSZINHERIT | XFS_DIFLAG_NODEFRAG | XFS_DIFLAG_FILESTREAM)

#endif  /* __XFS_DINODE_H__ */