fs/xfs/xfs_format.h

   1 /*
   2  * Copyright (c) 2000-2005 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_FORMAT_H__
  19 #define __XFS_FORMAT_H__
  20
  21 /*
  22  * XFS On Disk Format Definitions
  23  *
  24  * This header file defines all the on-disk format definitions for
  25  * general XFS objects. Directory and attribute related objects are defined in
  26  * xfs_da_format.h, which log and log item formats are defined in
  27  * xfs_log_format.h. Everything else goes here.
  28  */
  29
  30 struct xfs_mount;
  31 struct xfs_trans;
  32 struct xfs_inode;
  33 struct xfs_buf;
  34 struct xfs_ifork;
  35
  36 /*
  37  * RealTime Device format definitions
  38  */
  39
  40 /* Min and max rt extent sizes, specified in bytes */
  41 #define XFS_MAX_RTEXTSIZE       (1024 * 1024 * 1024)    /* 1GB */
  42 #define XFS_DFL_RTEXTSIZE       (64 * 1024)             /* 64kB */
  43 #define XFS_MIN_RTEXTSIZE       (4 * 1024)              /* 4kB */
  44
  45 #define XFS_BLOCKSIZE(mp)       ((mp)->m_sb.sb_blocksize)
  46 #define XFS_BLOCKMASK(mp)       ((mp)->m_blockmask)
  47 #define XFS_BLOCKWSIZE(mp)      ((mp)->m_blockwsize)
  48 #define XFS_BLOCKWMASK(mp)      ((mp)->m_blockwmask)
  49
  50 /*
  51  * RT Summary and bit manipulation macros.
  52  */
  53 #define XFS_SUMOFFS(mp,ls,bb)   ((int)((ls) * (mp)->m_sb.sb_rbmblocks + (bb)))
  54 #define XFS_SUMOFFSTOBLOCK(mp,s)        \
  55         (((s) * (uint)sizeof(xfs_suminfo_t)) >> (mp)->m_sb.sb_blocklog)
  56 #define XFS_SUMPTR(mp,bp,so)    \
  57         ((xfs_suminfo_t *)((bp)->b_addr + \
  58                 (((so) * (uint)sizeof(xfs_suminfo_t)) & XFS_BLOCKMASK(mp))))
  59
  60 #define XFS_BITTOBLOCK(mp,bi)   ((bi) >> (mp)->m_blkbit_log)
  61 #define XFS_BLOCKTOBIT(mp,bb)   ((bb) << (mp)->m_blkbit_log)
  62 #define XFS_BITTOWORD(mp,bi)    \
  63         ((int)(((bi) >> XFS_NBWORDLOG) & XFS_BLOCKWMASK(mp)))
  64
  65 #define XFS_RTMIN(a,b)  ((a) < (b) ? (a) : (b))
  66 #define XFS_RTMAX(a,b)  ((a) > (b) ? (a) : (b))
  67
  68 #define XFS_RTLOBIT(w)  xfs_lowbit32(w)
  69 #define XFS_RTHIBIT(w)  xfs_highbit32(w)
  70
  71 #if XFS_BIG_BLKNOS
  72 #define XFS_RTBLOCKLOG(b)       xfs_highbit64(b)
  73 #else
  74 #define XFS_RTBLOCKLOG(b)       xfs_highbit32(b)
  75 #endif
  76
  77 /*
  78  * Dquot and dquot block format definitions
  79  */
  80 #define XFS_DQUOT_MAGIC         0x4451          /* 'DQ' */
  81 #define XFS_DQUOT_VERSION       (u_int8_t)0x01  /* latest version number */
  82
  83 /*
  84  * This is the main portion of the on-disk representation of quota
  85  * information for a user. This is the q_core of the xfs_dquot_t that
  86  * is kept in kernel memory. We pad this with some more expansion room
  87  * to construct the on disk structure.
  88  */
  89 typedef struct  xfs_disk_dquot {
  90         __be16          d_magic;        /* dquot magic = XFS_DQUOT_MAGIC */
  91         __u8            d_version;      /* dquot version */
  92         __u8            d_flags;        /* XFS_DQ_USER/PROJ/GROUP */
  93         __be32          d_id;           /* user,project,group id */
  94         __be64          d_blk_hardlimit;/* absolute limit on disk blks */
  95         __be64          d_blk_softlimit;/* preferred limit on disk blks */
  96         __be64          d_ino_hardlimit;/* maximum # allocated inodes */
  97         __be64          d_ino_softlimit;/* preferred inode limit */
  98         __be64          d_bcount;       /* disk blocks owned by the user */
  99         __be64          d_icount;       /* inodes owned by the user */
 100         __be32          d_itimer;       /* zero if within inode limits if not,
 101                                            this is when we refuse service */
 102         __be32          d_btimer;       /* similar to above; for disk blocks */
 103         __be16          d_iwarns;       /* warnings issued wrt num inodes */
 104         __be16          d_bwarns;       /* warnings issued wrt disk blocks */
 105         __be32          d_pad0;         /* 64 bit align */
 106         __be64          d_rtb_hardlimit;/* absolute limit on realtime blks */
 107         __be64          d_rtb_softlimit;/* preferred limit on RT disk blks */
 108         __be64          d_rtbcount;     /* realtime blocks owned */
 109         __be32          d_rtbtimer;     /* similar to above; for RT disk blocks */
 110         __be16          d_rtbwarns;     /* warnings issued wrt RT disk blocks */
 111         __be16          d_pad;
 112 } xfs_disk_dquot_t;
 113
 114 /*
 115  * This is what goes on disk. This is separated from the xfs_disk_dquot because
 116  * carrying the unnecessary padding would be a waste of memory.
 117  */
 118 typedef struct xfs_dqblk {
 119         xfs_disk_dquot_t  dd_diskdq;    /* portion that lives incore as well */
 120         char              dd_fill[4];   /* filling for posterity */
 121
 122         /*
 123          * These two are only present on filesystems with the CRC bits set.
 124          */
 125         __be32            dd_crc;       /* checksum */
 126         __be64            dd_lsn;       /* last modification in log */
 127         uuid_t            dd_uuid;      /* location information */
 128 } xfs_dqblk_t;
 129
 130 #define XFS_DQUOT_CRC_OFF       offsetof(struct xfs_dqblk, dd_crc)
 131
 132 /*
 133  * Remote symlink format and access functions.
 134  */
 135 #define XFS_SYMLINK_MAGIC       0x58534c4d      /* XSLM */
 136
 137 struct xfs_dsymlink_hdr {
 138         __be32  sl_magic;
 139         __be32  sl_offset;
 140         __be32  sl_bytes;
 141         __be32  sl_crc;
 142         uuid_t  sl_uuid;
 143         __be64  sl_owner;
 144         __be64  sl_blkno;
 145         __be64  sl_lsn;
 146 };
 147
 148 /*
 149  * The maximum pathlen is 1024 bytes. Since the minimum file system
 150  * blocksize is 512 bytes, we can get a max of 3 extents back from
 151  * bmapi when crc headers are taken into account.
 152  */
 153 #define XFS_SYMLINK_MAPS 3
 154
 155 #define XFS_SYMLINK_BUF_SPACE(mp, bufsize)      \
 156         ((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \
 157                         sizeof(struct xfs_dsymlink_hdr) : 0))
 158
 159 int xfs_symlink_blocks(struct xfs_mount *mp, int pathlen);
 160 int xfs_symlink_hdr_set(struct xfs_mount *mp, xfs_ino_t ino, uint32_t offset,
 161                         uint32_t size, struct xfs_buf *bp);
 162 bool xfs_symlink_hdr_ok(struct xfs_mount *mp, xfs_ino_t ino, uint32_t offset,
 163                         uint32_t size, struct xfs_buf *bp);
 164 void xfs_symlink_local_to_remote(struct xfs_trans *tp, struct xfs_buf *bp,
 165                                  struct xfs_inode *ip, struct xfs_ifork *ifp);
 166
 167 extern const struct xfs_buf_ops xfs_symlink_buf_ops;
 168
 169 #endif /* __XFS_FORMAT_H__ */