/*
 * Copyright (c) 2000-2005 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_FORMAT_H__
#define __XFS_FORMAT_H__

/*
 * XFS On Disk Format Definitions
 *
 * This header file defines all the on-disk format definitions for 
 * general XFS objects. Directory and attribute related objects are defined in
 * xfs_da_format.h, which log and log item formats are defined in
 * xfs_log_format.h. Everything else goes here.
 */

struct xfs_mount;
struct xfs_trans;
struct xfs_inode;
struct xfs_buf;
struct xfs_ifork;

/*
 * RealTime Device format definitions
 */

/* Min and max rt extent sizes, specified in bytes */
#define XFS_MAX_RTEXTSIZE       (1024 * 1024 * 1024)    /* 1GB */
#define XFS_DFL_RTEXTSIZE       (64 * 1024)             /* 64kB */
#define XFS_MIN_RTEXTSIZE       (4 * 1024)              /* 4kB */

#define XFS_BLOCKSIZE(mp)       ((mp)->m_sb.sb_blocksize)
#define XFS_BLOCKMASK(mp)       ((mp)->m_blockmask)
#define XFS_BLOCKWSIZE(mp)      ((mp)->m_blockwsize)
#define XFS_BLOCKWMASK(mp)      ((mp)->m_blockwmask)

/*
 * RT Summary and bit manipulation macros.
 */
#define XFS_SUMOFFS(mp,ls,bb)   ((int)((ls) * (mp)->m_sb.sb_rbmblocks + (bb)))
#define XFS_SUMOFFSTOBLOCK(mp,s)        \
        (((s) * (uint)sizeof(xfs_suminfo_t)) >> (mp)->m_sb.sb_blocklog)
#define XFS_SUMPTR(mp,bp,so)    \
        ((xfs_suminfo_t *)((bp)->b_addr + \
                (((so) * (uint)sizeof(xfs_suminfo_t)) & XFS_BLOCKMASK(mp))))

#define XFS_BITTOBLOCK(mp,bi)   ((bi) >> (mp)->m_blkbit_log)
#define XFS_BLOCKTOBIT(mp,bb)   ((bb) << (mp)->m_blkbit_log)
#define XFS_BITTOWORD(mp,bi)    \
        ((int)(((bi) >> XFS_NBWORDLOG) & XFS_BLOCKWMASK(mp)))

#define XFS_RTMIN(a,b)  ((a) < (b) ? (a) : (b))
#define XFS_RTMAX(a,b)  ((a) > (b) ? (a) : (b))

#define XFS_RTLOBIT(w)  xfs_lowbit32(w)
#define XFS_RTHIBIT(w)  xfs_highbit32(w)

#if XFS_BIG_BLKNOS
#define XFS_RTBLOCKLOG(b)       xfs_highbit64(b)
#else
#define XFS_RTBLOCKLOG(b)       xfs_highbit32(b)
#endif

/*
 * Dquot and dquot block format definitions
 */
#define XFS_DQUOT_MAGIC         0x4451          /* 'DQ' */
#define XFS_DQUOT_VERSION       (u_int8_t)0x01  /* latest version number */

/*
 * This is the main portion of the on-disk representation of quota
 * information for a user. This is the q_core of the xfs_dquot_t that
 * is kept in kernel memory. We pad this with some more expansion room
 * to construct the on disk structure.
 */
typedef struct  xfs_disk_dquot {
        __be16          d_magic;        /* dquot magic = XFS_DQUOT_MAGIC */
        __u8            d_version;      /* dquot version */
        __u8            d_flags;        /* XFS_DQ_USER/PROJ/GROUP */
        __be32          d_id;           /* user,project,group id */
        __be64          d_blk_hardlimit;/* absolute limit on disk blks */
        __be64          d_blk_softlimit;/* preferred limit on disk blks */
        __be64          d_ino_hardlimit;/* maximum # allocated inodes */
        __be64          d_ino_softlimit;/* preferred inode limit */
        __be64          d_bcount;       /* disk blocks owned by the user */
        __be64          d_icount;       /* inodes owned by the user */
        __be32          d_itimer;       /* zero if within inode limits if not,
                                           this is when we refuse service */
        __be32          d_btimer;       /* similar to above; for disk blocks */
        __be16          d_iwarns;       /* warnings issued wrt num inodes */
        __be16          d_bwarns;       /* warnings issued wrt disk blocks */
        __be32          d_pad0;         /* 64 bit align */
        __be64          d_rtb_hardlimit;/* absolute limit on realtime blks */
        __be64          d_rtb_softlimit;/* preferred limit on RT disk blks */
        __be64          d_rtbcount;     /* realtime blocks owned */
        __be32          d_rtbtimer;     /* similar to above; for RT disk blocks */
        __be16          d_rtbwarns;     /* warnings issued wrt RT disk blocks */
        __be16          d_pad;
} xfs_disk_dquot_t;

/*
 * This is what goes on disk. This is separated from the xfs_disk_dquot because
 * carrying the unnecessary padding would be a waste of memory.
 */
typedef struct xfs_dqblk {
        xfs_disk_dquot_t  dd_diskdq;    /* portion that lives incore as well */
        char              dd_fill[4];   /* filling for posterity */

        /*
         * These two are only present on filesystems with the CRC bits set.
         */
        __be32            dd_crc;       /* checksum */
        __be64            dd_lsn;       /* last modification in log */
        uuid_t            dd_uuid;      /* location information */
} xfs_dqblk_t;

#define XFS_DQUOT_CRC_OFF       offsetof(struct xfs_dqblk, dd_crc)

/*
 * Remote symlink format and access functions.
 */
#define XFS_SYMLINK_MAGIC       0x58534c4d      /* XSLM */

struct xfs_dsymlink_hdr {
        __be32  sl_magic;
        __be32  sl_offset;
        __be32  sl_bytes;
        __be32  sl_crc;
        uuid_t  sl_uuid;
        __be64  sl_owner;
        __be64  sl_blkno;
        __be64  sl_lsn;
};

/*
 * The maximum pathlen is 1024 bytes. Since the minimum file system
 * blocksize is 512 bytes, we can get a max of 3 extents back from
 * bmapi when crc headers are taken into account.
 */
#define XFS_SYMLINK_MAPS 3

#define XFS_SYMLINK_BUF_SPACE(mp, bufsize)      \
        ((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \
                        sizeof(struct xfs_dsymlink_hdr) : 0))


/*
 * Allocation Btree format definitions
 *
 * There are two on-disk btrees, one sorted by blockno and one sorted
 * by blockcount and blockno.  All blocks look the same to make the code
 * simpler; if we have time later, we'll make the optimizations.
 */
#define XFS_ABTB_MAGIC          0x41425442      /* 'ABTB' for bno tree */
#define XFS_ABTB_CRC_MAGIC      0x41423342      /* 'AB3B' */
#define XFS_ABTC_MAGIC          0x41425443      /* 'ABTC' for cnt tree */
#define XFS_ABTC_CRC_MAGIC      0x41423343      /* 'AB3C' */

/*
 * Data record/key structure
 */
typedef struct xfs_alloc_rec {
        __be32          ar_startblock;  /* starting block number */
        __be32          ar_blockcount;  /* count of free blocks */
} xfs_alloc_rec_t, xfs_alloc_key_t;

typedef struct xfs_alloc_rec_incore {
        xfs_agblock_t   ar_startblock;  /* starting block number */
        xfs_extlen_t    ar_blockcount;  /* count of free blocks */
} xfs_alloc_rec_incore_t;

/* btree pointer type */
typedef __be32 xfs_alloc_ptr_t;

/*
 * Block numbers in the AG:
 * SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3.
 */
#define XFS_BNO_BLOCK(mp)       ((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1))
#define XFS_CNT_BLOCK(mp)       ((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))


/*
 * Inode Allocation Btree format definitions
 *
 * There is a btree for the inode map per allocation group.
 */
#define XFS_IBT_MAGIC           0x49414254      /* 'IABT' */
#define XFS_IBT_CRC_MAGIC       0x49414233      /* 'IAB3' */

typedef __uint64_t      xfs_inofree_t;
#define XFS_INODES_PER_CHUNK            (NBBY * sizeof(xfs_inofree_t))
#define XFS_INODES_PER_CHUNK_LOG        (XFS_NBBYLOG + 3)
#define XFS_INOBT_ALL_FREE              ((xfs_inofree_t)-1)
#define XFS_INOBT_MASK(i)               ((xfs_inofree_t)1 << (i))

static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
{
        return ((n >= XFS_INODES_PER_CHUNK ? 0 : XFS_INOBT_MASK(n)) - 1) << i;
}

/*
 * Data record structure
 */
typedef struct xfs_inobt_rec {
        __be32          ir_startino;    /* starting inode number */
        __be32          ir_freecount;   /* count of free inodes (set bits) */
        __be64          ir_free;        /* free inode mask */
} xfs_inobt_rec_t;

typedef struct xfs_inobt_rec_incore {
        xfs_agino_t     ir_startino;    /* starting inode number */
        __int32_t       ir_freecount;   /* count of free inodes (set bits) */
        xfs_inofree_t   ir_free;        /* free inode mask */
} xfs_inobt_rec_incore_t;


/*
 * Key structure
 */
typedef struct xfs_inobt_key {
        __be32          ir_startino;    /* starting inode number */
} xfs_inobt_key_t;

/* btree pointer type */
typedef __be32 xfs_inobt_ptr_t;

/*
 * block numbers in the AG.
 */
#define XFS_IBT_BLOCK(mp)               ((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1))
#define XFS_PREALLOC_BLOCKS(mp)         ((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))



/*
 * BMAP Btree format definitions
 *
 * This includes both the root block definition that sits inside an inode fork
 * and the record/pointer formats for the leaf/node in the blocks.
 */
#define XFS_BMAP_MAGIC          0x424d4150      /* 'BMAP' */
#define XFS_BMAP_CRC_MAGIC      0x424d4133      /* 'BMA3' */

/*
 * Bmap root header, on-disk form only.
 */
typedef struct xfs_bmdr_block {
        __be16          bb_level;       /* 0 is a leaf */
        __be16          bb_numrecs;     /* current # of data records */
} xfs_bmdr_block_t;

/*
 * Bmap btree record and extent descriptor.
 *  l0:63 is an extent flag (value 1 indicates non-normal).
 *  l0:9-62 are startoff.
 *  l0:0-8 and l1:21-63 are startblock.
 *  l1:0-20 are blockcount.
 */
#define BMBT_EXNTFLAG_BITLEN    1
#define BMBT_STARTOFF_BITLEN    54
#define BMBT_STARTBLOCK_BITLEN  52
#define BMBT_BLOCKCOUNT_BITLEN  21

typedef struct xfs_bmbt_rec {
        __be64                  l0, l1;
} xfs_bmbt_rec_t;

typedef __uint64_t      xfs_bmbt_rec_base_t;    /* use this for casts */
typedef xfs_bmbt_rec_t xfs_bmdr_rec_t;

typedef struct xfs_bmbt_rec_host {
        __uint64_t              l0, l1;
} xfs_bmbt_rec_host_t;

/*
 * Values and macros for delayed-allocation startblock fields.
 */
#define STARTBLOCKVALBITS       17
#define STARTBLOCKMASKBITS      (15 + XFS_BIG_BLKNOS * 20)
#define DSTARTBLOCKMASKBITS     (15 + 20)
#define STARTBLOCKMASK          \
        (((((xfs_fsblock_t)1) << STARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
#define DSTARTBLOCKMASK         \
        (((((xfs_dfsbno_t)1) << DSTARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)

static inline int isnullstartblock(xfs_fsblock_t x)
{
        return ((x) & STARTBLOCKMASK) == STARTBLOCKMASK;
}

static inline int isnulldstartblock(xfs_dfsbno_t x)
{
        return ((x) & DSTARTBLOCKMASK) == DSTARTBLOCKMASK;
}

static inline xfs_fsblock_t nullstartblock(int k)
{
        ASSERT(k < (1 << STARTBLOCKVALBITS));
        return STARTBLOCKMASK | (k);
}

static inline xfs_filblks_t startblockval(xfs_fsblock_t x)
{
        return (xfs_filblks_t)((x) & ~STARTBLOCKMASK);
}

/*
 * Possible extent formats.
 */
typedef enum {
        XFS_EXTFMT_NOSTATE = 0,
        XFS_EXTFMT_HASSTATE
} xfs_exntfmt_t;

/*
 * Possible extent states.
 */
typedef enum {
        XFS_EXT_NORM, XFS_EXT_UNWRITTEN,
        XFS_EXT_DMAPI_OFFLINE, XFS_EXT_INVALID
} xfs_exntst_t;

/*
 * Incore version of above.
 */
typedef struct xfs_bmbt_irec
{
        xfs_fileoff_t   br_startoff;    /* starting file offset */
        xfs_fsblock_t   br_startblock;  /* starting block number */
        xfs_filblks_t   br_blockcount;  /* number of blocks */
        xfs_exntst_t    br_state;       /* extent state */
} xfs_bmbt_irec_t;

/*
 * Key structure for non-leaf levels of the tree.
 */
typedef struct xfs_bmbt_key {
        __be64          br_startoff;    /* starting file offset */
} xfs_bmbt_key_t, xfs_bmdr_key_t;

/* btree pointer type */
typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t;


/*
 * Generic Btree block format definitions
 *
 * This is a combination of the actual format used on disk for short and long
 * format btrees.  The first three fields are shared by both format, but the
 * pointers are different and should be used with care.
 *
 * To get the size of the actual short or long form headers please use the size
 * macros below.  Never use sizeof(xfs_btree_block).
 *
 * The blkno, crc, lsn, owner and uuid fields are only available in filesystems
 * with the crc feature bit, and all accesses to them must be conditional on
 * that flag.
 */
struct xfs_btree_block {
        __be32          bb_magic;       /* magic number for block type */
        __be16          bb_level;       /* 0 is a leaf */
        __be16          bb_numrecs;     /* current # of data records */
        union {
                struct {
                        __be32          bb_leftsib;
                        __be32          bb_rightsib;

                        __be64          bb_blkno;
                        __be64          bb_lsn;
                        uuid_t          bb_uuid;
                        __be32          bb_owner;
                        __le32          bb_crc;
                } s;                    /* short form pointers */
                struct  {
                        __be64          bb_leftsib;
                        __be64          bb_rightsib;

                        __be64          bb_blkno;
                        __be64          bb_lsn;
                        uuid_t          bb_uuid;
                        __be64          bb_owner;
                        __le32          bb_crc;
                        __be32          bb_pad; /* padding for alignment */
                } l;                    /* long form pointers */
        } bb_u;                         /* rest */
};

#define XFS_BTREE_SBLOCK_LEN    16      /* size of a short form block */
#define XFS_BTREE_LBLOCK_LEN    24      /* size of a long form block */

/* sizes of CRC enabled btree blocks */
#define XFS_BTREE_SBLOCK_CRC_LEN        (XFS_BTREE_SBLOCK_LEN + 40)
#define XFS_BTREE_LBLOCK_CRC_LEN        (XFS_BTREE_LBLOCK_LEN + 48)

#define XFS_BTREE_SBLOCK_CRC_OFF \
        offsetof(struct xfs_btree_block, bb_u.s.bb_crc)
#define XFS_BTREE_LBLOCK_CRC_OFF \
        offsetof(struct xfs_btree_block, bb_u.l.bb_crc)

#endif /* __XFS_FORMAT_H__ */