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root/fs/xfs/xfs_trans.h

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INCLUDED FROM


DEFINITIONS

This source file includes following definitions.
  1. xfs_lic_init
  2. xfs_lic_init_slot
  3. xfs_lic_vacancy
  4. xfs_lic_all_free
  5. xfs_lic_are_all_free
  6. xfs_lic_isfree
  7. xfs_lic_claim
  8. xfs_lic_relse
  9. xfs_lic_slot
  10. xfs_lic_desc_to_slot
  11. xfs_lic_desc_to_chunk

/*
 * 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_TRANS_H__
#define __XFS_TRANS_H__

/*
 * This is the structure written in the log at the head of
 * every transaction. It identifies the type and id of the
 * transaction, and contains the number of items logged by
 * the transaction so we know how many to expect during recovery.
 *
 * Do not change the below structure without redoing the code in
 * xlog_recover_add_to_trans() and xlog_recover_add_to_cont_trans().
 */
typedef struct xfs_trans_header {
        uint            th_magic;               /* magic number */
        uint            th_type;                /* transaction type */
        __int32_t       th_tid;                 /* transaction id (unused) */
        uint            th_num_items;           /* num items logged by trans */
} xfs_trans_header_t;

#define XFS_TRANS_HEADER_MAGIC  0x5452414e      /* TRAN */

/*
 * Log item types.
 */
#define XFS_LI_EFI              0x1236
#define XFS_LI_EFD              0x1237
#define XFS_LI_IUNLINK          0x1238
#define XFS_LI_INODE            0x123b  /* aligned ino chunks, var-size ibufs */
#define XFS_LI_BUF              0x123c  /* v2 bufs, variable sized inode bufs */
#define XFS_LI_DQUOT            0x123d
#define XFS_LI_QUOTAOFF         0x123e

/*
 * Transaction types.  Used to distinguish types of buffers.
 */
#define XFS_TRANS_SETATTR_NOT_SIZE      1
#define XFS_TRANS_SETATTR_SIZE          2
#define XFS_TRANS_INACTIVE              3
#define XFS_TRANS_CREATE                4
#define XFS_TRANS_CREATE_TRUNC          5
#define XFS_TRANS_TRUNCATE_FILE         6
#define XFS_TRANS_REMOVE                7
#define XFS_TRANS_LINK                  8
#define XFS_TRANS_RENAME                9
#define XFS_TRANS_MKDIR                 10
#define XFS_TRANS_RMDIR                 11
#define XFS_TRANS_SYMLINK               12
#define XFS_TRANS_SET_DMATTRS           13
#define XFS_TRANS_GROWFS                14
#define XFS_TRANS_STRAT_WRITE           15
#define XFS_TRANS_DIOSTRAT              16
#define XFS_TRANS_WRITE_SYNC            17
#define XFS_TRANS_WRITEID               18
#define XFS_TRANS_ADDAFORK              19
#define XFS_TRANS_ATTRINVAL             20
#define XFS_TRANS_ATRUNCATE             21
#define XFS_TRANS_ATTR_SET              22
#define XFS_TRANS_ATTR_RM               23
#define XFS_TRANS_ATTR_FLAG             24
#define XFS_TRANS_CLEAR_AGI_BUCKET      25
#define XFS_TRANS_QM_SBCHANGE           26
/*
 * Dummy entries since we use the transaction type to index into the
 * trans_type[] in xlog_recover_print_trans_head()
 */
#define XFS_TRANS_DUMMY1                27
#define XFS_TRANS_DUMMY2                28
#define XFS_TRANS_QM_QUOTAOFF           29
#define XFS_TRANS_QM_DQALLOC            30
#define XFS_TRANS_QM_SETQLIM            31
#define XFS_TRANS_QM_DQCLUSTER          32
#define XFS_TRANS_QM_QINOCREATE         33
#define XFS_TRANS_QM_QUOTAOFF_END       34
#define XFS_TRANS_SB_UNIT               35
#define XFS_TRANS_FSYNC_TS              36
#define XFS_TRANS_GROWFSRT_ALLOC        37
#define XFS_TRANS_GROWFSRT_ZERO         38
#define XFS_TRANS_GROWFSRT_FREE         39
#define XFS_TRANS_SWAPEXT               40
#define XFS_TRANS_SB_COUNT              41
#define XFS_TRANS_TYPE_MAX              41
/* new transaction types need to be reflected in xfs_logprint(8) */


#ifdef __KERNEL__
struct xfs_buf;
struct xfs_buftarg;
struct xfs_efd_log_item;
struct xfs_efi_log_item;
struct xfs_inode;
struct xfs_item_ops;
struct xfs_log_iovec;
struct xfs_log_item;
struct xfs_log_item_desc;
struct xfs_mount;
struct xfs_trans;
struct xfs_dquot_acct;

typedef struct xfs_log_item {
        struct list_head                li_ail;         /* AIL pointers */
        xfs_lsn_t                       li_lsn;         /* last on-disk lsn */
        struct xfs_log_item_desc        *li_desc;       /* ptr to current desc*/
        struct xfs_mount                *li_mountp;     /* ptr to fs mount */
        uint                            li_type;        /* item type */
        uint                            li_flags;       /* misc flags */
        struct xfs_log_item             *li_bio_list;   /* buffer item list */
        void                            (*li_cb)(struct xfs_buf *,
                                                 struct xfs_log_item *);
                                                        /* buffer item iodone */
                                                        /* callback func */
        struct xfs_item_ops             *li_ops;        /* function list */
} xfs_log_item_t;

#define XFS_LI_IN_AIL   0x1
#define XFS_LI_ABORTED  0x2

typedef struct xfs_item_ops {
        uint (*iop_size)(xfs_log_item_t *);
        void (*iop_format)(xfs_log_item_t *, struct xfs_log_iovec *);
        void (*iop_pin)(xfs_log_item_t *);
        void (*iop_unpin)(xfs_log_item_t *, int);
        void (*iop_unpin_remove)(xfs_log_item_t *, struct xfs_trans *);
        uint (*iop_trylock)(xfs_log_item_t *);
        void (*iop_unlock)(xfs_log_item_t *);
        xfs_lsn_t (*iop_committed)(xfs_log_item_t *, xfs_lsn_t);
        void (*iop_push)(xfs_log_item_t *);
        void (*iop_pushbuf)(xfs_log_item_t *);
        void (*iop_committing)(xfs_log_item_t *, xfs_lsn_t);
} xfs_item_ops_t;

#define IOP_SIZE(ip)            (*(ip)->li_ops->iop_size)(ip)
#define IOP_FORMAT(ip,vp)       (*(ip)->li_ops->iop_format)(ip, vp)
#define IOP_PIN(ip)             (*(ip)->li_ops->iop_pin)(ip)
#define IOP_UNPIN(ip, flags)    (*(ip)->li_ops->iop_unpin)(ip, flags)
#define IOP_UNPIN_REMOVE(ip,tp) (*(ip)->li_ops->iop_unpin_remove)(ip, tp)
#define IOP_TRYLOCK(ip)         (*(ip)->li_ops->iop_trylock)(ip)
#define IOP_UNLOCK(ip)          (*(ip)->li_ops->iop_unlock)(ip)
#define IOP_COMMITTED(ip, lsn)  (*(ip)->li_ops->iop_committed)(ip, lsn)
#define IOP_PUSH(ip)            (*(ip)->li_ops->iop_push)(ip)
#define IOP_PUSHBUF(ip)         (*(ip)->li_ops->iop_pushbuf)(ip)
#define IOP_COMMITTING(ip, lsn) (*(ip)->li_ops->iop_committing)(ip, lsn)

/*
 * Return values for the IOP_TRYLOCK() routines.
 */
#define XFS_ITEM_SUCCESS        0
#define XFS_ITEM_PINNED         1
#define XFS_ITEM_LOCKED         2
#define XFS_ITEM_FLUSHING       3
#define XFS_ITEM_PUSHBUF        4

#endif  /* __KERNEL__ */

/*
 * This structure is used to track log items associated with
 * a transaction.  It points to the log item and keeps some
 * flags to track the state of the log item.  It also tracks
 * the amount of space needed to log the item it describes
 * once we get to commit processing (see xfs_trans_commit()).
 */
typedef struct xfs_log_item_desc {
        xfs_log_item_t  *lid_item;
        ushort          lid_size;
        unsigned char   lid_flags;
        unsigned char   lid_index;
} xfs_log_item_desc_t;

#define XFS_LID_DIRTY           0x1
#define XFS_LID_PINNED          0x2
#define XFS_LID_BUF_STALE       0x8

/*
 * This structure is used to maintain a chunk list of log_item_desc
 * structures. The free field is a bitmask indicating which descriptors
 * in this chunk's array are free.  The unused field is the first value
 * not used since this chunk was allocated.
 */
#define XFS_LIC_NUM_SLOTS       15
typedef struct xfs_log_item_chunk {
        struct xfs_log_item_chunk       *lic_next;
        ushort                          lic_free;
        ushort                          lic_unused;
        xfs_log_item_desc_t             lic_descs[XFS_LIC_NUM_SLOTS];
} xfs_log_item_chunk_t;

#define XFS_LIC_MAX_SLOT        (XFS_LIC_NUM_SLOTS - 1)
#define XFS_LIC_FREEMASK        ((1 << XFS_LIC_NUM_SLOTS) - 1)


/*
 * Initialize the given chunk.  Set the chunk's free descriptor mask
 * to indicate that all descriptors are free.  The caller gets to set
 * lic_unused to the right value (0 matches all free).  The
 * lic_descs.lid_index values are set up as each desc is allocated.
 */
static inline void xfs_lic_init(xfs_log_item_chunk_t *cp)
{
        cp->lic_free = XFS_LIC_FREEMASK;
}

static inline void xfs_lic_init_slot(xfs_log_item_chunk_t *cp, int slot)
{
        cp->lic_descs[slot].lid_index = (unsigned char)(slot);
}

static inline int xfs_lic_vacancy(xfs_log_item_chunk_t *cp)
{
        return cp->lic_free & XFS_LIC_FREEMASK;
}

static inline void xfs_lic_all_free(xfs_log_item_chunk_t *cp)
{
        cp->lic_free = XFS_LIC_FREEMASK;
}

static inline int xfs_lic_are_all_free(xfs_log_item_chunk_t *cp)
{
        return ((cp->lic_free & XFS_LIC_FREEMASK) == XFS_LIC_FREEMASK);
}

static inline int xfs_lic_isfree(xfs_log_item_chunk_t *cp, int slot)
{
        return (cp->lic_free & (1 << slot));
}

static inline void xfs_lic_claim(xfs_log_item_chunk_t *cp, int slot)
{
        cp->lic_free &= ~(1 << slot);
}

static inline void xfs_lic_relse(xfs_log_item_chunk_t *cp, int slot)
{
        cp->lic_free |= 1 << slot;
}

static inline xfs_log_item_desc_t *
xfs_lic_slot(xfs_log_item_chunk_t *cp, int slot)
{
        return &(cp->lic_descs[slot]);
}

static inline int xfs_lic_desc_to_slot(xfs_log_item_desc_t *dp)
{
        return (uint)dp->lid_index;
}

/*
 * Calculate the address of a chunk given a descriptor pointer:
 * dp - dp->lid_index give the address of the start of the lic_descs array.
 * From this we subtract the offset of the lic_descs field in a chunk.
 * All of this yields the address of the chunk, which is
 * cast to a chunk pointer.
 */
static inline xfs_log_item_chunk_t *
xfs_lic_desc_to_chunk(xfs_log_item_desc_t *dp)
{
        return (xfs_log_item_chunk_t*) \
                (((xfs_caddr_t)((dp) - (dp)->lid_index)) - \
                (xfs_caddr_t)(((xfs_log_item_chunk_t*)0)->lic_descs));
}

#ifdef __KERNEL__
/*
 * This structure is used to maintain a list of block ranges that have been
 * freed in the transaction.  The ranges are listed in the perag[] busy list
 * between when they're freed and the transaction is committed to disk.
 */

typedef struct xfs_log_busy_slot {
        xfs_agnumber_t          lbc_ag;
        ushort                  lbc_idx;        /* index in perag.busy[] */
} xfs_log_busy_slot_t;

#define XFS_LBC_NUM_SLOTS       31
typedef struct xfs_log_busy_chunk {
        struct xfs_log_busy_chunk       *lbc_next;
        uint                            lbc_free;       /* free slots bitmask */
        ushort                          lbc_unused;     /* first unused */
        xfs_log_busy_slot_t             lbc_busy[XFS_LBC_NUM_SLOTS];
} xfs_log_busy_chunk_t;

#define XFS_LBC_MAX_SLOT        (XFS_LBC_NUM_SLOTS - 1)
#define XFS_LBC_FREEMASK        ((1U << XFS_LBC_NUM_SLOTS) - 1)

#define XFS_LBC_INIT(cp)        ((cp)->lbc_free = XFS_LBC_FREEMASK)
#define XFS_LBC_CLAIM(cp, slot) ((cp)->lbc_free &= ~(1 << (slot)))
#define XFS_LBC_SLOT(cp, slot)  (&((cp)->lbc_busy[(slot)]))
#define XFS_LBC_VACANCY(cp)     (((cp)->lbc_free) & XFS_LBC_FREEMASK)
#define XFS_LBC_ISFREE(cp, slot) ((cp)->lbc_free & (1 << (slot)))

/*
 * This is the type of function which can be given to xfs_trans_callback()
 * to be called upon the transaction's commit to disk.
 */
typedef void (*xfs_trans_callback_t)(struct xfs_trans *, void *);

/*
 * This is the structure maintained for every active transaction.
 */
typedef struct xfs_trans {
        unsigned int            t_magic;        /* magic number */
        xfs_log_callback_t      t_logcb;        /* log callback struct */
        unsigned int            t_type;         /* transaction type */
        unsigned int            t_log_res;      /* amt of log space resvd */
        unsigned int            t_log_count;    /* count for perm log res */
        unsigned int            t_blk_res;      /* # of blocks resvd */
        unsigned int            t_blk_res_used; /* # of resvd blocks used */
        unsigned int            t_rtx_res;      /* # of rt extents resvd */
        unsigned int            t_rtx_res_used; /* # of resvd rt extents used */
        xfs_log_ticket_t        t_ticket;       /* log mgr ticket */
        xfs_lsn_t               t_lsn;          /* log seq num of start of
                                                 * transaction. */
        xfs_lsn_t               t_commit_lsn;   /* log seq num of end of
                                                 * transaction. */
        struct xfs_mount        *t_mountp;      /* ptr to fs mount struct */
        struct xfs_dquot_acct   *t_dqinfo;      /* acctg info for dquots */
        xfs_trans_callback_t    t_callback;     /* transaction callback */
        void                    *t_callarg;     /* callback arg */
        unsigned int            t_flags;        /* misc flags */
        int64_t                 t_icount_delta; /* superblock icount change */
        int64_t                 t_ifree_delta;  /* superblock ifree change */
        int64_t                 t_fdblocks_delta; /* superblock fdblocks chg */
        int64_t                 t_res_fdblocks_delta; /* on-disk only chg */
        int64_t                 t_frextents_delta;/* superblock freextents chg*/
        int64_t                 t_res_frextents_delta; /* on-disk only chg */
#ifdef DEBUG
        int64_t                 t_ag_freeblks_delta; /* debugging counter */
        int64_t                 t_ag_flist_delta; /* debugging counter */
        int64_t                 t_ag_btree_delta; /* debugging counter */
#endif
        int64_t                 t_dblocks_delta;/* superblock dblocks change */
        int64_t                 t_agcount_delta;/* superblock agcount change */
        int64_t                 t_imaxpct_delta;/* superblock imaxpct change */
        int64_t                 t_rextsize_delta;/* superblock rextsize chg */
        int64_t                 t_rbmblocks_delta;/* superblock rbmblocks chg */
        int64_t                 t_rblocks_delta;/* superblock rblocks change */
        int64_t                 t_rextents_delta;/* superblocks rextents chg */
        int64_t                 t_rextslog_delta;/* superblocks rextslog chg */
        unsigned int            t_items_free;   /* log item descs free */
        xfs_log_item_chunk_t    t_items;        /* first log item desc chunk */
        xfs_trans_header_t      t_header;       /* header for in-log trans */
        unsigned int            t_busy_free;    /* busy descs free */
        xfs_log_busy_chunk_t    t_busy;         /* busy/async free blocks */
        unsigned long           t_pflags;       /* saved process flags state */
} xfs_trans_t;

#endif  /* __KERNEL__ */


#define XFS_TRANS_MAGIC         0x5452414E      /* 'TRAN' */
/*
 * Values for t_flags.
 */
#define XFS_TRANS_DIRTY         0x01    /* something needs to be logged */
#define XFS_TRANS_SB_DIRTY      0x02    /* superblock is modified */
#define XFS_TRANS_PERM_LOG_RES  0x04    /* xact took a permanent log res */
#define XFS_TRANS_SYNC          0x08    /* make commit synchronous */
#define XFS_TRANS_DQ_DIRTY      0x10    /* at least one dquot in trx dirty */
#define XFS_TRANS_RESERVE       0x20    /* OK to use reserved data blocks */

/*
 * Values for call flags parameter.
 */
#define XFS_TRANS_NOSLEEP               0x1
#define XFS_TRANS_WAIT                  0x2
#define XFS_TRANS_RELEASE_LOG_RES       0x4
#define XFS_TRANS_ABORT                 0x8

/*
 * Field values for xfs_trans_mod_sb.
 */
#define XFS_TRANS_SB_ICOUNT             0x00000001
#define XFS_TRANS_SB_IFREE              0x00000002
#define XFS_TRANS_SB_FDBLOCKS           0x00000004
#define XFS_TRANS_SB_RES_FDBLOCKS       0x00000008
#define XFS_TRANS_SB_FREXTENTS          0x00000010
#define XFS_TRANS_SB_RES_FREXTENTS      0x00000020
#define XFS_TRANS_SB_DBLOCKS            0x00000040
#define XFS_TRANS_SB_AGCOUNT            0x00000080
#define XFS_TRANS_SB_IMAXPCT            0x00000100
#define XFS_TRANS_SB_REXTSIZE           0x00000200
#define XFS_TRANS_SB_RBMBLOCKS          0x00000400
#define XFS_TRANS_SB_RBLOCKS            0x00000800
#define XFS_TRANS_SB_REXTENTS           0x00001000
#define XFS_TRANS_SB_REXTSLOG           0x00002000


/*
 * Various log reservation values.
 * These are based on the size of the file system block
 * because that is what most transactions manipulate.
 * Each adds in an additional 128 bytes per item logged to
 * try to account for the overhead of the transaction mechanism.
 *
 * Note:
 * Most of the reservations underestimate the number of allocation
 * groups into which they could free extents in the xfs_bmap_finish()
 * call.  This is because the number in the worst case is quite high
 * and quite unusual.  In order to fix this we need to change
 * xfs_bmap_finish() to free extents in only a single AG at a time.
 * This will require changes to the EFI code as well, however, so that
 * the EFI for the extents not freed is logged again in each transaction.
 * See bug 261917.
 */

/*
 * Per-extent log reservation for the allocation btree changes
 * involved in freeing or allocating an extent.
 * 2 trees * (2 blocks/level * max depth - 1) * block size
 */
#define XFS_ALLOCFREE_LOG_RES(mp,nx) \
        ((nx) * (2 * XFS_FSB_TO_B((mp), 2 * XFS_AG_MAXLEVELS(mp) - 1)))
#define XFS_ALLOCFREE_LOG_COUNT(mp,nx) \
        ((nx) * (2 * (2 * XFS_AG_MAXLEVELS(mp) - 1)))

/*
 * Per-directory log reservation for any directory change.
 * dir blocks: (1 btree block per level + data block + free block) * dblock size
 * bmap btree: (levels + 2) * max depth * block size
 * v2 directory blocks can be fragmented below the dirblksize down to the fsb
 * size, so account for that in the DAENTER macros.
 */
#define XFS_DIROP_LOG_RES(mp)   \
        (XFS_FSB_TO_B(mp, XFS_DAENTER_BLOCKS(mp, XFS_DATA_FORK)) + \
         (XFS_FSB_TO_B(mp, XFS_DAENTER_BMAPS(mp, XFS_DATA_FORK) + 1)))
#define XFS_DIROP_LOG_COUNT(mp) \
        (XFS_DAENTER_BLOCKS(mp, XFS_DATA_FORK) + \
         XFS_DAENTER_BMAPS(mp, XFS_DATA_FORK) + 1)

/*
 * In a write transaction we can allocate a maximum of 2
 * extents.  This gives:
 *    the inode getting the new extents: inode size
 *    the inode\'s bmap btree: max depth * block size
 *    the agfs of the ags from which the extents are allocated: 2 * sector
 *    the superblock free block counter: sector size
 *    the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
 * And the bmap_finish transaction can free bmap blocks in a join:
 *    the agfs of the ags containing the blocks: 2 * sector size
 *    the agfls of the ags containing the blocks: 2 * sector size
 *    the super block free block counter: sector size
 *    the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
 */
#define XFS_CALC_WRITE_LOG_RES(mp) \
        (MAX( \
         ((mp)->m_sb.sb_inodesize + \
          XFS_FSB_TO_B((mp), XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK)) + \
          (2 * (mp)->m_sb.sb_sectsize) + \
          (mp)->m_sb.sb_sectsize + \
          XFS_ALLOCFREE_LOG_RES(mp, 2) + \
          (128 * (4 + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) + XFS_ALLOCFREE_LOG_COUNT(mp, 2)))),\
         ((2 * (mp)->m_sb.sb_sectsize) + \
          (2 * (mp)->m_sb.sb_sectsize) + \
          (mp)->m_sb.sb_sectsize + \
          XFS_ALLOCFREE_LOG_RES(mp, 2) + \
          (128 * (5 + XFS_ALLOCFREE_LOG_COUNT(mp, 2))))))

#define XFS_WRITE_LOG_RES(mp)   ((mp)->m_reservations.tr_write)

/*
 * In truncating a file we free up to two extents at once.  We can modify:
 *    the inode being truncated: inode size
 *    the inode\'s bmap btree: (max depth + 1) * block size
 * And the bmap_finish transaction can free the blocks and bmap blocks:
 *    the agf for each of the ags: 4 * sector size
 *    the agfl for each of the ags: 4 * sector size
 *    the super block to reflect the freed blocks: sector size
 *    worst case split in allocation btrees per extent assuming 4 extents:
 *              4 exts * 2 trees * (2 * max depth - 1) * block size
 *    the inode btree: max depth * blocksize
 *    the allocation btrees: 2 trees * (max depth - 1) * block size
 */
#define XFS_CALC_ITRUNCATE_LOG_RES(mp) \
        (MAX( \
         ((mp)->m_sb.sb_inodesize + \
          XFS_FSB_TO_B((mp), XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) + 1) + \
          (128 * (2 + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK)))), \
         ((4 * (mp)->m_sb.sb_sectsize) + \
          (4 * (mp)->m_sb.sb_sectsize) + \
          (mp)->m_sb.sb_sectsize + \
          XFS_ALLOCFREE_LOG_RES(mp, 4) + \
          (128 * (9 + XFS_ALLOCFREE_LOG_COUNT(mp, 4))) + \
          (128 * 5) + \
          XFS_ALLOCFREE_LOG_RES(mp, 1) + \
           (128 * (2 + XFS_IALLOC_BLOCKS(mp) + XFS_IN_MAXLEVELS(mp) + \
            XFS_ALLOCFREE_LOG_COUNT(mp, 1))))))

#define XFS_ITRUNCATE_LOG_RES(mp)   ((mp)->m_reservations.tr_itruncate)

/*
 * In renaming a files we can modify:
 *    the four inodes involved: 4 * inode size
 *    the two directory btrees: 2 * (max depth + v2) * dir block size
 *    the two directory bmap btrees: 2 * max depth * block size
 * And the bmap_finish transaction can free dir and bmap blocks (two sets
 *      of bmap blocks) giving:
 *    the agf for the ags in which the blocks live: 3 * sector size
 *    the agfl for the ags in which the blocks live: 3 * sector size
 *    the superblock for the free block count: sector size
 *    the allocation btrees: 3 exts * 2 trees * (2 * max depth - 1) * block size
 */
#define XFS_CALC_RENAME_LOG_RES(mp) \
        (MAX( \
         ((4 * (mp)->m_sb.sb_inodesize) + \
          (2 * XFS_DIROP_LOG_RES(mp)) + \
          (128 * (4 + 2 * XFS_DIROP_LOG_COUNT(mp)))), \
         ((3 * (mp)->m_sb.sb_sectsize) + \
          (3 * (mp)->m_sb.sb_sectsize) + \
          (mp)->m_sb.sb_sectsize + \
          XFS_ALLOCFREE_LOG_RES(mp, 3) + \
          (128 * (7 + XFS_ALLOCFREE_LOG_COUNT(mp, 3))))))

#define XFS_RENAME_LOG_RES(mp)  ((mp)->m_reservations.tr_rename)

/*
 * For creating a link to an inode:
 *    the parent directory inode: inode size
 *    the linked inode: inode size
 *    the directory btree could split: (max depth + v2) * dir block size
 *    the directory bmap btree could join or split: (max depth + v2) * blocksize
 * And the bmap_finish transaction can free some bmap blocks giving:
 *    the agf for the ag in which the blocks live: sector size
 *    the agfl for the ag in which the blocks live: sector size
 *    the superblock for the free block count: sector size
 *    the allocation btrees: 2 trees * (2 * max depth - 1) * block size
 */
#define XFS_CALC_LINK_LOG_RES(mp) \
        (MAX( \
         ((mp)->m_sb.sb_inodesize + \
          (mp)->m_sb.sb_inodesize + \
          XFS_DIROP_LOG_RES(mp) + \
          (128 * (2 + XFS_DIROP_LOG_COUNT(mp)))), \
         ((mp)->m_sb.sb_sectsize + \
          (mp)->m_sb.sb_sectsize + \
          (mp)->m_sb.sb_sectsize + \
          XFS_ALLOCFREE_LOG_RES(mp, 1) + \
          (128 * (3 + XFS_ALLOCFREE_LOG_COUNT(mp, 1))))))

#define XFS_LINK_LOG_RES(mp)    ((mp)->m_reservations.tr_link)

/*
 * For removing a directory entry we can modify:
 *    the parent directory inode: inode size
 *    the removed inode: inode size
 *    the directory btree could join: (max depth + v2) * dir block size
 *    the directory bmap btree could join or split: (max depth + v2) * blocksize
 * And the bmap_finish transaction can free the dir and bmap blocks giving:
 *    the agf for the ag in which the blocks live: 2 * sector size
 *    the agfl for the ag in which the blocks live: 2 * sector size
 *    the superblock for the free block count: sector size
 *    the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
 */
#define XFS_CALC_REMOVE_LOG_RES(mp)     \
        (MAX( \
         ((mp)->m_sb.sb_inodesize + \
          (mp)->m_sb.sb_inodesize + \
          XFS_DIROP_LOG_RES(mp) + \
          (128 * (2 + XFS_DIROP_LOG_COUNT(mp)))), \
         ((2 * (mp)->m_sb.sb_sectsize) + \
          (2 * (mp)->m_sb.sb_sectsize) + \
          (mp)->m_sb.sb_sectsize + \
          XFS_ALLOCFREE_LOG_RES(mp, 2) + \
          (128 * (5 + XFS_ALLOCFREE_LOG_COUNT(mp, 2))))))

#define XFS_REMOVE_LOG_RES(mp)  ((mp)->m_reservations.tr_remove)

/*
 * For symlink we can modify:
 *    the parent directory inode: inode size
 *    the new inode: inode size
 *    the inode btree entry: 1 block
 *    the directory btree: (max depth + v2) * dir block size
 *    the directory inode\'s bmap btree: (max depth + v2) * block size
 *    the blocks for the symlink: 1 KB
 * Or in the first xact we allocate some inodes giving:
 *    the agi and agf of the ag getting the new inodes: 2 * sectorsize
 *    the inode blocks allocated: XFS_IALLOC_BLOCKS * blocksize
 *    the inode btree: max depth * blocksize
 *    the allocation btrees: 2 trees * (2 * max depth - 1) * block size
 */
#define XFS_CALC_SYMLINK_LOG_RES(mp)            \
        (MAX( \
         ((mp)->m_sb.sb_inodesize + \
          (mp)->m_sb.sb_inodesize + \
          XFS_FSB_TO_B(mp, 1) + \
          XFS_DIROP_LOG_RES(mp) + \
          1024 + \
          (128 * (4 + XFS_DIROP_LOG_COUNT(mp)))), \
         (2 * (mp)->m_sb.sb_sectsize + \
          XFS_FSB_TO_B((mp), XFS_IALLOC_BLOCKS((mp))) + \
          XFS_FSB_TO_B((mp), XFS_IN_MAXLEVELS(mp)) + \
          XFS_ALLOCFREE_LOG_RES(mp, 1) + \
          (128 * (2 + XFS_IALLOC_BLOCKS(mp) + XFS_IN_MAXLEVELS(mp) + \
           XFS_ALLOCFREE_LOG_COUNT(mp, 1))))))

#define XFS_SYMLINK_LOG_RES(mp) ((mp)->m_reservations.tr_symlink)

/*
 * For create we can modify:
 *    the parent directory inode: inode size
 *    the new inode: inode size
 *    the inode btree entry: block size
 *    the superblock for the nlink flag: sector size
 *    the directory btree: (max depth + v2) * dir block size
 *    the directory inode\'s bmap btree: (max depth + v2) * block size
 * Or in the first xact we allocate some inodes giving:
 *    the agi and agf of the ag getting the new inodes: 2 * sectorsize
 *    the superblock for the nlink flag: sector size
 *    the inode blocks allocated: XFS_IALLOC_BLOCKS * blocksize
 *    the inode btree: max depth * blocksize
 *    the allocation btrees: 2 trees * (max depth - 1) * block size
 */
#define XFS_CALC_CREATE_LOG_RES(mp)             \
        (MAX( \
         ((mp)->m_sb.sb_inodesize + \
          (mp)->m_sb.sb_inodesize + \
          (mp)->m_sb.sb_sectsize + \
          XFS_FSB_TO_B(mp, 1) + \
          XFS_DIROP_LOG_RES(mp) + \
          (128 * (3 + XFS_DIROP_LOG_COUNT(mp)))), \
         (3 * (mp)->m_sb.sb_sectsize + \
          XFS_FSB_TO_B((mp), XFS_IALLOC_BLOCKS((mp))) + \
          XFS_FSB_TO_B((mp), XFS_IN_MAXLEVELS(mp)) + \
          XFS_ALLOCFREE_LOG_RES(mp, 1) + \
          (128 * (2 + XFS_IALLOC_BLOCKS(mp) + XFS_IN_MAXLEVELS(mp) + \
           XFS_ALLOCFREE_LOG_COUNT(mp, 1))))))

#define XFS_CREATE_LOG_RES(mp)  ((mp)->m_reservations.tr_create)

/*
 * Making a new directory is the same as creating a new file.
 */
#define XFS_CALC_MKDIR_LOG_RES(mp)      XFS_CALC_CREATE_LOG_RES(mp)

#define XFS_MKDIR_LOG_RES(mp)   ((mp)->m_reservations.tr_mkdir)

/*
 * In freeing an inode we can modify:
 *    the inode being freed: inode size
 *    the super block free inode counter: sector size
 *    the agi hash list and counters: sector size
 *    the inode btree entry: block size
 *    the on disk inode before ours in the agi hash list: inode cluster size
 *    the inode btree: max depth * blocksize
 *    the allocation btrees: 2 trees * (max depth - 1) * block size
 */
#define XFS_CALC_IFREE_LOG_RES(mp) \
        ((mp)->m_sb.sb_inodesize + \
         (mp)->m_sb.sb_sectsize + \
         (mp)->m_sb.sb_sectsize + \
         XFS_FSB_TO_B((mp), 1) + \
         MAX((__uint16_t)XFS_FSB_TO_B((mp), 1), XFS_INODE_CLUSTER_SIZE(mp)) + \
         (128 * 5) + \
          XFS_ALLOCFREE_LOG_RES(mp, 1) + \
          (128 * (2 + XFS_IALLOC_BLOCKS(mp) + XFS_IN_MAXLEVELS(mp) + \
           XFS_ALLOCFREE_LOG_COUNT(mp, 1))))


#define XFS_IFREE_LOG_RES(mp)   ((mp)->m_reservations.tr_ifree)

/*
 * When only changing the inode we log the inode and possibly the superblock
 * We also add a bit of slop for the transaction stuff.
 */
#define XFS_CALC_ICHANGE_LOG_RES(mp)    ((mp)->m_sb.sb_inodesize + \
                                         (mp)->m_sb.sb_sectsize + 512)

#define XFS_ICHANGE_LOG_RES(mp) ((mp)->m_reservations.tr_ichange)

/*
 * Growing the data section of the filesystem.
 *      superblock
 *      agi and agf
 *      allocation btrees
 */
#define XFS_CALC_GROWDATA_LOG_RES(mp) \
        ((mp)->m_sb.sb_sectsize * 3 + \
         XFS_ALLOCFREE_LOG_RES(mp, 1) + \
         (128 * (3 + XFS_ALLOCFREE_LOG_COUNT(mp, 1))))

#define XFS_GROWDATA_LOG_RES(mp)    ((mp)->m_reservations.tr_growdata)

/*
 * Growing the rt section of the filesystem.
 * In the first set of transactions (ALLOC) we allocate space to the
 * bitmap or summary files.
 *      superblock: sector size
 *      agf of the ag from which the extent is allocated: sector size
 *      bmap btree for bitmap/summary inode: max depth * blocksize
 *      bitmap/summary inode: inode size
 *      allocation btrees for 1 block alloc: 2 * (2 * maxdepth - 1) * blocksize
 */
#define XFS_CALC_GROWRTALLOC_LOG_RES(mp) \
        (2 * (mp)->m_sb.sb_sectsize + \
         XFS_FSB_TO_B((mp), XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK)) + \
         (mp)->m_sb.sb_inodesize + \
         XFS_ALLOCFREE_LOG_RES(mp, 1) + \
         (128 * \
          (3 + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) + \
           XFS_ALLOCFREE_LOG_COUNT(mp, 1))))

#define XFS_GROWRTALLOC_LOG_RES(mp)     ((mp)->m_reservations.tr_growrtalloc)

/*
 * Growing the rt section of the filesystem.
 * In the second set of transactions (ZERO) we zero the new metadata blocks.
 *      one bitmap/summary block: blocksize
 */
#define XFS_CALC_GROWRTZERO_LOG_RES(mp) \
        ((mp)->m_sb.sb_blocksize + 128)

#define XFS_GROWRTZERO_LOG_RES(mp)      ((mp)->m_reservations.tr_growrtzero)

/*
 * Growing the rt section of the filesystem.
 * In the third set of transactions (FREE) we update metadata without
 * allocating any new blocks.
 *      superblock: sector size
 *      bitmap inode: inode size
 *      summary inode: inode size
 *      one bitmap block: blocksize
 *      summary blocks: new summary size
 */
#define XFS_CALC_GROWRTFREE_LOG_RES(mp) \
        ((mp)->m_sb.sb_sectsize + \
         2 * (mp)->m_sb.sb_inodesize + \
         (mp)->m_sb.sb_blocksize + \
         (mp)->m_rsumsize + \
         (128 * 5))

#define XFS_GROWRTFREE_LOG_RES(mp)      ((mp)->m_reservations.tr_growrtfree)

/*
 * Logging the inode modification timestamp on a synchronous write.
 *      inode
 */
#define XFS_CALC_SWRITE_LOG_RES(mp) \
        ((mp)->m_sb.sb_inodesize + 128)

#define XFS_SWRITE_LOG_RES(mp)  ((mp)->m_reservations.tr_swrite)

/*
 * Logging the inode timestamps on an fsync -- same as SWRITE
 * as long as SWRITE logs the entire inode core
 */
#define XFS_FSYNC_TS_LOG_RES(mp)        ((mp)->m_reservations.tr_swrite)

/*
 * Logging the inode mode bits when writing a setuid/setgid file
 *      inode
 */
#define XFS_CALC_WRITEID_LOG_RES(mp) \
        ((mp)->m_sb.sb_inodesize + 128)

#define XFS_WRITEID_LOG_RES(mp) ((mp)->m_reservations.tr_swrite)

/*
 * Converting the inode from non-attributed to attributed.
 *      the inode being converted: inode size
 *      agf block and superblock (for block allocation)
 *      the new block (directory sized)
 *      bmap blocks for the new directory block
 *      allocation btrees
 */
#define XFS_CALC_ADDAFORK_LOG_RES(mp)   \
        ((mp)->m_sb.sb_inodesize + \
         (mp)->m_sb.sb_sectsize * 2 + \
         (mp)->m_dirblksize + \
         XFS_FSB_TO_B(mp, (XFS_DAENTER_BMAP1B(mp, XFS_DATA_FORK) + 1)) + \
         XFS_ALLOCFREE_LOG_RES(mp, 1) + \
         (128 * (4 + (XFS_DAENTER_BMAP1B(mp, XFS_DATA_FORK) + 1) + \
                 XFS_ALLOCFREE_LOG_COUNT(mp, 1))))

#define XFS_ADDAFORK_LOG_RES(mp)        ((mp)->m_reservations.tr_addafork)

/*
 * Removing the attribute fork of a file
 *    the inode being truncated: inode size
 *    the inode\'s bmap btree: max depth * block size
 * And the bmap_finish transaction can free the blocks and bmap blocks:
 *    the agf for each of the ags: 4 * sector size
 *    the agfl for each of the ags: 4 * sector size
 *    the super block to reflect the freed blocks: sector size
 *    worst case split in allocation btrees per extent assuming 4 extents:
 *              4 exts * 2 trees * (2 * max depth - 1) * block size
 */
#define XFS_CALC_ATTRINVAL_LOG_RES(mp)  \
        (MAX( \
         ((mp)->m_sb.sb_inodesize + \
          XFS_FSB_TO_B((mp), XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK)) + \
          (128 * (1 + XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK)))), \
         ((4 * (mp)->m_sb.sb_sectsize) + \
          (4 * (mp)->m_sb.sb_sectsize) + \
          (mp)->m_sb.sb_sectsize + \
          XFS_ALLOCFREE_LOG_RES(mp, 4) + \
          (128 * (9 + XFS_ALLOCFREE_LOG_COUNT(mp, 4))))))

#define XFS_ATTRINVAL_LOG_RES(mp)       ((mp)->m_reservations.tr_attrinval)

/*
 * Setting an attribute.
 *      the inode getting the attribute
 *      the superblock for allocations
 *      the agfs extents are allocated from
 *      the attribute btree * max depth
 *      the inode allocation btree
 * Since attribute transaction space is dependent on the size of the attribute,
 * the calculation is done partially at mount time and partially at runtime.
 */
#define XFS_CALC_ATTRSET_LOG_RES(mp)    \
        ((mp)->m_sb.sb_inodesize + \
         (mp)->m_sb.sb_sectsize + \
          XFS_FSB_TO_B((mp), XFS_DA_NODE_MAXDEPTH) + \
          (128 * (2 + XFS_DA_NODE_MAXDEPTH)))

#define XFS_ATTRSET_LOG_RES(mp, ext)    \
        ((mp)->m_reservations.tr_attrset + \
         (ext * (mp)->m_sb.sb_sectsize) + \
         (ext * XFS_FSB_TO_B((mp), XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK))) + \
         (128 * (ext + (ext * XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK)))))

/*
 * Removing an attribute.
 *    the inode: inode size
 *    the attribute btree could join: max depth * block size
 *    the inode bmap btree could join or split: max depth * block size
 * And the bmap_finish transaction can free the attr blocks freed giving:
 *    the agf for the ag in which the blocks live: 2 * sector size
 *    the agfl for the ag in which the blocks live: 2 * sector size
 *    the superblock for the free block count: sector size
 *    the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
 */
#define XFS_CALC_ATTRRM_LOG_RES(mp)     \
        (MAX( \
          ((mp)->m_sb.sb_inodesize + \
          XFS_FSB_TO_B((mp), XFS_DA_NODE_MAXDEPTH) + \
          XFS_FSB_TO_B((mp), XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK)) + \
          (128 * (1 + XFS_DA_NODE_MAXDEPTH + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK)))), \
         ((2 * (mp)->m_sb.sb_sectsize) + \
          (2 * (mp)->m_sb.sb_sectsize) + \
          (mp)->m_sb.sb_sectsize + \
          XFS_ALLOCFREE_LOG_RES(mp, 2) + \
          (128 * (5 + XFS_ALLOCFREE_LOG_COUNT(mp, 2))))))

#define XFS_ATTRRM_LOG_RES(mp)  ((mp)->m_reservations.tr_attrrm)

/*
 * Clearing a bad agino number in an agi hash bucket.
 */
#define XFS_CALC_CLEAR_AGI_BUCKET_LOG_RES(mp) \
        ((mp)->m_sb.sb_sectsize + 128)

#define XFS_CLEAR_AGI_BUCKET_LOG_RES(mp)  ((mp)->m_reservations.tr_clearagi)


/*
 * Various log count values.
 */
#define XFS_DEFAULT_LOG_COUNT           1
#define XFS_DEFAULT_PERM_LOG_COUNT      2
#define XFS_ITRUNCATE_LOG_COUNT         2
#define XFS_INACTIVE_LOG_COUNT          2
#define XFS_CREATE_LOG_COUNT            2
#define XFS_MKDIR_LOG_COUNT             3
#define XFS_SYMLINK_LOG_COUNT           3
#define XFS_REMOVE_LOG_COUNT            2
#define XFS_LINK_LOG_COUNT              2
#define XFS_RENAME_LOG_COUNT            2
#define XFS_WRITE_LOG_COUNT             2
#define XFS_ADDAFORK_LOG_COUNT          2
#define XFS_ATTRINVAL_LOG_COUNT         1
#define XFS_ATTRSET_LOG_COUNT           3
#define XFS_ATTRRM_LOG_COUNT            3

/*
 * Here we centralize the specification of XFS meta-data buffer
 * reference count values.  This determine how hard the buffer
 * cache tries to hold onto the buffer.
 */
#define XFS_AGF_REF             4
#define XFS_AGI_REF             4
#define XFS_AGFL_REF            3
#define XFS_INO_BTREE_REF       3
#define XFS_ALLOC_BTREE_REF     2
#define XFS_BMAP_BTREE_REF      2
#define XFS_DIR_BTREE_REF       2
#define XFS_ATTR_BTREE_REF      1
#define XFS_INO_REF             1
#define XFS_DQUOT_REF           1

#ifdef __KERNEL__
/*
 * XFS transaction mechanism exported interfaces that are
 * actually macros.
 */
#define xfs_trans_get_log_res(tp)       ((tp)->t_log_res)
#define xfs_trans_get_log_count(tp)     ((tp)->t_log_count)
#define xfs_trans_get_block_res(tp)     ((tp)->t_blk_res)
#define xfs_trans_set_sync(tp)          ((tp)->t_flags |= XFS_TRANS_SYNC)

#ifdef DEBUG
#define xfs_trans_agblocks_delta(tp, d) ((tp)->t_ag_freeblks_delta += (int64_t)d)
#define xfs_trans_agflist_delta(tp, d)  ((tp)->t_ag_flist_delta += (int64_t)d)
#define xfs_trans_agbtree_delta(tp, d)  ((tp)->t_ag_btree_delta += (int64_t)d)
#else
#define xfs_trans_agblocks_delta(tp, d)
#define xfs_trans_agflist_delta(tp, d)
#define xfs_trans_agbtree_delta(tp, d)
#endif

/*
 * XFS transaction mechanism exported interfaces.
 */
void            xfs_trans_init(struct xfs_mount *);
xfs_trans_t     *xfs_trans_alloc(struct xfs_mount *, uint);
xfs_trans_t     *_xfs_trans_alloc(struct xfs_mount *, uint);
xfs_trans_t     *xfs_trans_dup(xfs_trans_t *);
int             xfs_trans_reserve(xfs_trans_t *, uint, uint, uint,
                                  uint, uint);
void            xfs_trans_mod_sb(xfs_trans_t *, uint, int64_t);
struct xfs_buf  *xfs_trans_get_buf(xfs_trans_t *, struct xfs_buftarg *, xfs_daddr_t,
                                   int, uint);
int             xfs_trans_read_buf(struct xfs_mount *, xfs_trans_t *,
                                   struct xfs_buftarg *, xfs_daddr_t, int, uint,
                                   struct xfs_buf **);
struct xfs_buf  *xfs_trans_getsb(xfs_trans_t *, struct xfs_mount *, int);

void            xfs_trans_brelse(xfs_trans_t *, struct xfs_buf *);
void            xfs_trans_bjoin(xfs_trans_t *, struct xfs_buf *);
void            xfs_trans_bhold(xfs_trans_t *, struct xfs_buf *);
void            xfs_trans_bhold_release(xfs_trans_t *, struct xfs_buf *);
void            xfs_trans_binval(xfs_trans_t *, struct xfs_buf *);
void            xfs_trans_inode_buf(xfs_trans_t *, struct xfs_buf *);
void            xfs_trans_stale_inode_buf(xfs_trans_t *, struct xfs_buf *);
void            xfs_trans_dquot_buf(xfs_trans_t *, struct xfs_buf *, uint);
void            xfs_trans_inode_alloc_buf(xfs_trans_t *, struct xfs_buf *);
int             xfs_trans_iget(struct xfs_mount *, xfs_trans_t *,
                               xfs_ino_t , uint, uint, struct xfs_inode **);
void            xfs_trans_ijoin(xfs_trans_t *, struct xfs_inode *, uint);
void            xfs_trans_ihold(xfs_trans_t *, struct xfs_inode *);
void            xfs_trans_log_buf(xfs_trans_t *, struct xfs_buf *, uint, uint);
void            xfs_trans_log_inode(xfs_trans_t *, struct xfs_inode *, uint);
struct xfs_efi_log_item *xfs_trans_get_efi(xfs_trans_t *, uint);
void            xfs_efi_release(struct xfs_efi_log_item *, uint);
void            xfs_trans_log_efi_extent(xfs_trans_t *,
                                         struct xfs_efi_log_item *,
                                         xfs_fsblock_t,
                                         xfs_extlen_t);
struct xfs_efd_log_item *xfs_trans_get_efd(xfs_trans_t *,
                                  struct xfs_efi_log_item *,
                                  uint);
void            xfs_trans_log_efd_extent(xfs_trans_t *,
                                         struct xfs_efd_log_item *,
                                         xfs_fsblock_t,
                                         xfs_extlen_t);
int             _xfs_trans_commit(xfs_trans_t *,
                                  uint flags,
                                  int *);
#define xfs_trans_commit(tp, flags)     _xfs_trans_commit(tp, flags, NULL)
void            xfs_trans_cancel(xfs_trans_t *, int);
int             xfs_trans_roll(struct xfs_trans **, struct xfs_inode *);
int             xfs_trans_ail_init(struct xfs_mount *);
void            xfs_trans_ail_destroy(struct xfs_mount *);
void            xfs_trans_push_ail(struct xfs_mount *, xfs_lsn_t);
xfs_lsn_t       xfs_trans_tail_ail(struct xfs_mount *);
void            xfs_trans_unlocked_item(struct xfs_mount *,
                                        xfs_log_item_t *);
xfs_log_busy_slot_t *xfs_trans_add_busy(xfs_trans_t *tp,
                                        xfs_agnumber_t ag,
                                        xfs_extlen_t idx);

extern kmem_zone_t      *xfs_trans_zone;

#endif  /* __KERNEL__ */

#endif  /* __XFS_TRANS_H__ */

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