fs/xfs/xfs_dinode.h

   1 /*
   2  * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #ifndef __XFS_DINODE_H__
  19 #define __XFS_DINODE_H__
  20
  21 #define XFS_DINODE_MAGIC                0x494e  /* 'IN' */
  22 #define XFS_DINODE_GOOD_VERSION(v)      ((v) >= 1 && (v) <= 3)
  23
  24 typedef struct xfs_timestamp {
  25         __be32          t_sec;          /* timestamp seconds */
  26         __be32          t_nsec;         /* timestamp nanoseconds */
  27 } xfs_timestamp_t;
  28
  29 /*
  30  * On-disk inode structure.
  31  *
  32  * This is just the header or "dinode core", the inode is expanded to fill a
  33  * variable size the leftover area split into a data and an attribute fork.
  34  * The format of the data and attribute fork depends on the format of the
  35  * inode as indicated by di_format and di_aformat.  To access the data and
  36  * attribute use the XFS_DFORK_DPTR, XFS_DFORK_APTR, and XFS_DFORK_PTR macros
  37  * below.
  38  *
  39  * There is a very similar struct icdinode in xfs_inode which matches the
  40  * layout of the first 96 bytes of this structure, but is kept in native
  41  * format instead of big endian.
  42  *
  43  * Note: di_flushiter is only used by v1/2 inodes - it's effectively a zeroed
  44  * padding field for v3 inodes.
  45  */
  46 typedef struct xfs_dinode {
  47         __be16          di_magic;       /* inode magic # = XFS_DINODE_MAGIC */
  48         __be16          di_mode;        /* mode and type of file */
  49         __u8            di_version;     /* inode version */
  50         __u8            di_format;      /* format of di_c data */
  51         __be16          di_onlink;      /* old number of links to file */
  52         __be32          di_uid;         /* owner's user id */
  53         __be32          di_gid;         /* owner's group id */
  54         __be32          di_nlink;       /* number of links to file */
  55         __be16          di_projid_lo;   /* lower part of owner's project id */
  56         __be16          di_projid_hi;   /* higher part owner's project id */
  57         __u8            di_pad[6];      /* unused, zeroed space */
  58         __be16          di_flushiter;   /* incremented on flush */
  59         xfs_timestamp_t di_atime;       /* time last accessed */
  60         xfs_timestamp_t di_mtime;       /* time last modified */
  61         xfs_timestamp_t di_ctime;       /* time created/inode modified */
  62         __be64          di_size;        /* number of bytes in file */
  63         __be64          di_nblocks;     /* # of direct & btree blocks used */
  64         __be32          di_extsize;     /* basic/minimum extent size for file */
  65         __be32          di_nextents;    /* number of extents in data fork */
  66         __be16          di_anextents;   /* number of extents in attribute fork*/
  67         __u8            di_forkoff;     /* attr fork offs, <<3 for 64b align */
  68         __s8            di_aformat;     /* format of attr fork's data */
  69         __be32          di_dmevmask;    /* DMIG event mask */
  70         __be16          di_dmstate;     /* DMIG state info */
  71         __be16          di_flags;       /* random flags, XFS_DIFLAG_... */
  72         __be32          di_gen;         /* generation number */
  73
  74         /* di_next_unlinked is the only non-core field in the old dinode */
  75         __be32          di_next_unlinked;/* agi unlinked list ptr */
  76
  77         /* start of the extended dinode, writable fields */
  78         __le32          di_crc;         /* CRC of the inode */
  79         __be64          di_changecount; /* number of attribute changes */
  80         __be64          di_lsn;         /* flush sequence */
  81         __be64          di_flags2;      /* more random flags */
  82         __u8            di_pad2[16];    /* more padding for future expansion */
  83
  84         /* fields only written to during inode creation */
  85         xfs_timestamp_t di_crtime;      /* time created */
  86         __be64          di_ino;         /* inode number */
  87         uuid_t          di_uuid;        /* UUID of the filesystem */
  88
  89         /* structure must be padded to 64 bit alignment */
  90 } xfs_dinode_t;
  91
  92 #define DI_MAX_FLUSH 0xffff
  93
  94 /*
  95  * Size of the core inode on disk.  Version 1 and 2 inodes have
  96  * the same size, but version 3 has grown a few additional fields.
  97  */
  98 static inline uint xfs_dinode_size(int version)
  99 {
 100         if (version == 3)
 101                 return sizeof(struct xfs_dinode);
 102         return offsetof(struct xfs_dinode, di_crc);
 103 }
 104
 105 /*
 106  * The 32 bit link count in the inode theoretically maxes out at UINT_MAX.
 107  * Since the pathconf interface is signed, we use 2^31 - 1 instead.
 108  * The old inode format had a 16 bit link count, so its maximum is USHRT_MAX.
 109  */
 110 #define XFS_MAXLINK             ((1U << 31) - 1U)
 111 #define XFS_MAXLINK_1           65535U
 112
 113 /*
 114  * Values for di_format
 115  */
 116 typedef enum xfs_dinode_fmt {
 117         XFS_DINODE_FMT_DEV,             /* xfs_dev_t */
 118         XFS_DINODE_FMT_LOCAL,           /* bulk data */
 119         XFS_DINODE_FMT_EXTENTS,         /* struct xfs_bmbt_rec */
 120         XFS_DINODE_FMT_BTREE,           /* struct xfs_bmdr_block */
 121         XFS_DINODE_FMT_UUID             /* uuid_t */
 122 } xfs_dinode_fmt_t;
 123
 124 /*
 125  * Inode minimum and maximum sizes.
 126  */
 127 #define XFS_DINODE_MIN_LOG      8
 128 #define XFS_DINODE_MAX_LOG      11
 129 #define XFS_DINODE_MIN_SIZE     (1 << XFS_DINODE_MIN_LOG)
 130 #define XFS_DINODE_MAX_SIZE     (1 << XFS_DINODE_MAX_LOG)
 131
 132 /*
 133  * Inode size for given fs.
 134  */
 135 #define XFS_LITINO(mp, version) \
 136         ((int)(((mp)->m_sb.sb_inodesize) - xfs_dinode_size(version)))
 137
 138 /*
 139  * Inode data & attribute fork sizes, per inode.
 140  */
 141 #define XFS_DFORK_Q(dip)                ((dip)->di_forkoff != 0)
 142 #define XFS_DFORK_BOFF(dip)             ((int)((dip)->di_forkoff << 3))
 143
 144 #define XFS_DFORK_DSIZE(dip,mp) \
 145         (XFS_DFORK_Q(dip) ? \
 146                 XFS_DFORK_BOFF(dip) : \
 147                 XFS_LITINO(mp, (dip)->di_version))
 148 #define XFS_DFORK_ASIZE(dip,mp) \
 149         (XFS_DFORK_Q(dip) ? \
 150                 XFS_LITINO(mp, (dip)->di_version) - XFS_DFORK_BOFF(dip) : \
 151                 0)
 152 #define XFS_DFORK_SIZE(dip,mp,w) \
 153         ((w) == XFS_DATA_FORK ? \
 154                 XFS_DFORK_DSIZE(dip, mp) : \
 155                 XFS_DFORK_ASIZE(dip, mp))
 156
 157 /*
 158  * Return pointers to the data or attribute forks.
 159  */
 160 #define XFS_DFORK_DPTR(dip) \
 161         ((char *)dip + xfs_dinode_size(dip->di_version))
 162 #define XFS_DFORK_APTR(dip)     \
 163         (XFS_DFORK_DPTR(dip) + XFS_DFORK_BOFF(dip))
 164 #define XFS_DFORK_PTR(dip,w)    \
 165         ((w) == XFS_DATA_FORK ? XFS_DFORK_DPTR(dip) : XFS_DFORK_APTR(dip))
 166
 167 #define XFS_DFORK_FORMAT(dip,w) \
 168         ((w) == XFS_DATA_FORK ? \
 169                 (dip)->di_format : \
 170                 (dip)->di_aformat)
 171 #define XFS_DFORK_NEXTENTS(dip,w) \
 172         ((w) == XFS_DATA_FORK ? \
 173                 be32_to_cpu((dip)->di_nextents) : \
 174                 be16_to_cpu((dip)->di_anextents))
 175
 176 #define XFS_BUF_TO_DINODE(bp)   ((xfs_dinode_t *)((bp)->b_addr))
 177
 178 /*
 179  * For block and character special files the 32bit dev_t is stored at the
 180  * beginning of the data fork.
 181  */
 182 static inline xfs_dev_t xfs_dinode_get_rdev(struct xfs_dinode *dip)
 183 {
 184         return be32_to_cpu(*(__be32 *)XFS_DFORK_DPTR(dip));
 185 }
 186
 187 static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
 188 {
 189         *(__be32 *)XFS_DFORK_DPTR(dip) = cpu_to_be32(rdev);
 190 }
 191
 192 /*
 193  * Values for di_flags
 194  * There should be a one-to-one correspondence between these flags and the
 195  * XFS_XFLAG_s.
 196  */
 197 #define XFS_DIFLAG_REALTIME_BIT  0      /* file's blocks come from rt area */
 198 #define XFS_DIFLAG_PREALLOC_BIT  1      /* file space has been preallocated */
 199 #define XFS_DIFLAG_NEWRTBM_BIT   2      /* for rtbitmap inode, new format */
 200 #define XFS_DIFLAG_IMMUTABLE_BIT 3      /* inode is immutable */
 201 #define XFS_DIFLAG_APPEND_BIT    4      /* inode is append-only */
 202 #define XFS_DIFLAG_SYNC_BIT      5      /* inode is written synchronously */
 203 #define XFS_DIFLAG_NOATIME_BIT   6      /* do not update atime */
 204 #define XFS_DIFLAG_NODUMP_BIT    7      /* do not dump */
 205 #define XFS_DIFLAG_RTINHERIT_BIT 8      /* create with realtime bit set */
 206 #define XFS_DIFLAG_PROJINHERIT_BIT   9  /* create with parents projid */
 207 #define XFS_DIFLAG_NOSYMLINKS_BIT   10  /* disallow symlink creation */
 208 #define XFS_DIFLAG_EXTSIZE_BIT      11  /* inode extent size allocator hint */
 209 #define XFS_DIFLAG_EXTSZINHERIT_BIT 12  /* inherit inode extent size */
 210 #define XFS_DIFLAG_NODEFRAG_BIT     13  /* do not reorganize/defragment */
 211 #define XFS_DIFLAG_FILESTREAM_BIT   14  /* use filestream allocator */
 212 #define XFS_DIFLAG_REALTIME      (1 << XFS_DIFLAG_REALTIME_BIT)
 213 #define XFS_DIFLAG_PREALLOC      (1 << XFS_DIFLAG_PREALLOC_BIT)
 214 #define XFS_DIFLAG_NEWRTBM       (1 << XFS_DIFLAG_NEWRTBM_BIT)
 215 #define XFS_DIFLAG_IMMUTABLE     (1 << XFS_DIFLAG_IMMUTABLE_BIT)
 216 #define XFS_DIFLAG_APPEND        (1 << XFS_DIFLAG_APPEND_BIT)
 217 #define XFS_DIFLAG_SYNC          (1 << XFS_DIFLAG_SYNC_BIT)
 218 #define XFS_DIFLAG_NOATIME       (1 << XFS_DIFLAG_NOATIME_BIT)
 219 #define XFS_DIFLAG_NODUMP        (1 << XFS_DIFLAG_NODUMP_BIT)
 220 #define XFS_DIFLAG_RTINHERIT     (1 << XFS_DIFLAG_RTINHERIT_BIT)
 221 #define XFS_DIFLAG_PROJINHERIT   (1 << XFS_DIFLAG_PROJINHERIT_BIT)
 222 #define XFS_DIFLAG_NOSYMLINKS    (1 << XFS_DIFLAG_NOSYMLINKS_BIT)
 223 #define XFS_DIFLAG_EXTSIZE       (1 << XFS_DIFLAG_EXTSIZE_BIT)
 224 #define XFS_DIFLAG_EXTSZINHERIT  (1 << XFS_DIFLAG_EXTSZINHERIT_BIT)
 225 #define XFS_DIFLAG_NODEFRAG      (1 << XFS_DIFLAG_NODEFRAG_BIT)
 226 #define XFS_DIFLAG_FILESTREAM    (1 << XFS_DIFLAG_FILESTREAM_BIT)
 227
 228 #ifdef CONFIG_XFS_RT
 229 #define XFS_IS_REALTIME_INODE(ip) ((ip)->i_d.di_flags & XFS_DIFLAG_REALTIME)
 230 #else
 231 #define XFS_IS_REALTIME_INODE(ip) (0)
 232 #endif
 233
 234 #define XFS_DIFLAG_ANY \
 235         (XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \
 236          XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \
 237          XFS_DIFLAG_NOATIME | XFS_DIFLAG_NODUMP | XFS_DIFLAG_RTINHERIT | \
 238          XFS_DIFLAG_PROJINHERIT | XFS_DIFLAG_NOSYMLINKS | XFS_DIFLAG_EXTSIZE | \
 239          XFS_DIFLAG_EXTSZINHERIT | XFS_DIFLAG_NODEFRAG | XFS_DIFLAG_FILESTREAM)
 240
 241 #endif  /* __XFS_DINODE_H__ */