/*
 * Copyright (c) 2000-2006 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_BMAP_H__
#define __XFS_BMAP_H__

struct getbmap;
struct xfs_bmbt_irec;
struct xfs_ifork;
struct xfs_inode;
struct xfs_mount;
struct xfs_trans;

extern kmem_zone_t      *xfs_bmap_free_item_zone;

/*
 * Argument structure for xfs_bmap_alloc.
 */
struct xfs_bmalloca {
        xfs_fsblock_t           *firstblock; /* i/o first block allocated */
        struct xfs_defer_ops    *dfops; /* bmap freelist */
        struct xfs_trans        *tp;    /* transaction pointer */
        struct xfs_inode        *ip;    /* incore inode pointer */
        struct xfs_bmbt_irec    prev;   /* extent before the new one */
        struct xfs_bmbt_irec    got;    /* extent after, or delayed */

        xfs_fileoff_t           offset; /* offset in file filling in */
        xfs_extlen_t            length; /* i/o length asked/allocated */
        xfs_fsblock_t           blkno;  /* starting block of new extent */

        struct xfs_btree_cur    *cur;   /* btree cursor */
        xfs_extnum_t            idx;    /* current extent index */
        int                     nallocs;/* number of extents alloc'd */
        int                     logflags;/* flags for transaction logging */

        xfs_extlen_t            total;  /* total blocks needed for xaction */
        xfs_extlen_t            minlen; /* minimum allocation size (blocks) */
        xfs_extlen_t            minleft; /* amount must be left after alloc */
        bool                    eof;    /* set if allocating past last extent */
        bool                    wasdel; /* replacing a delayed allocation */
        bool                    aeof;   /* allocated space at eof */
        bool                    conv;   /* overwriting unwritten extents */
        int                     datatype;/* data type being allocated */
        int                     flags;
};

/*
 * List of extents to be free "later".
 * The list is kept sorted on xbf_startblock.
 */
struct xfs_extent_free_item
{
        xfs_fsblock_t           xefi_startblock;/* starting fs block number */
        xfs_extlen_t            xefi_blockcount;/* number of blocks in extent */
        struct list_head        xefi_list;
        struct xfs_owner_info   xefi_oinfo;     /* extent owner */
};

#define XFS_BMAP_MAX_NMAP       4

/*
 * Flags for xfs_bmapi_*
 */
#define XFS_BMAPI_ENTIRE        0x001   /* return entire extent, not trimmed */
#define XFS_BMAPI_METADATA      0x002   /* mapping metadata not user data */
#define XFS_BMAPI_ATTRFORK      0x004   /* use attribute fork not data */
#define XFS_BMAPI_PREALLOC      0x008   /* preallocation op: unwritten space */
#define XFS_BMAPI_IGSTATE       0x010   /* Ignore state - */
                                        /* combine contig. space */
#define XFS_BMAPI_CONTIG        0x020   /* must allocate only one extent */
/*
 * unwritten extent conversion - this needs write cache flushing and no additional
 * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
 * from written to unwritten, otherwise convert from unwritten to written.
 */
#define XFS_BMAPI_CONVERT       0x040

/*
 * allocate zeroed extents - this requires all newly allocated user data extents
 * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
 * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
 * during the allocation range to zeroed written extents.
 */
#define XFS_BMAPI_ZERO          0x080

/*
 * Map the inode offset to the block given in ap->firstblock.  Primarily
 * used for reflink.  The range must be in a hole, and this flag cannot be
 * turned on with PREALLOC or CONVERT, and cannot be used on the attr fork.
 *
 * For bunmapi, this flag unmaps the range without adjusting quota, reducing
 * refcount, or freeing the blocks.
 */
#define XFS_BMAPI_REMAP         0x100

/* Map something in the CoW fork. */
#define XFS_BMAPI_COWFORK       0x200

/* Only convert delalloc space, don't allocate entirely new extents */
#define XFS_BMAPI_DELALLOC      0x400

#define XFS_BMAPI_FLAGS \
        { XFS_BMAPI_ENTIRE,     "ENTIRE" }, \
        { XFS_BMAPI_METADATA,   "METADATA" }, \
        { XFS_BMAPI_ATTRFORK,   "ATTRFORK" }, \
        { XFS_BMAPI_PREALLOC,   "PREALLOC" }, \
        { XFS_BMAPI_IGSTATE,    "IGSTATE" }, \
        { XFS_BMAPI_CONTIG,     "CONTIG" }, \
        { XFS_BMAPI_CONVERT,    "CONVERT" }, \
        { XFS_BMAPI_ZERO,       "ZERO" }, \
        { XFS_BMAPI_REMAP,      "REMAP" }, \
        { XFS_BMAPI_COWFORK,    "COWFORK" }, \
        { XFS_BMAPI_DELALLOC,   "DELALLOC" }


static inline int xfs_bmapi_aflag(int w)
{
        return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK :
               (w == XFS_COW_FORK ? XFS_BMAPI_COWFORK : 0));
}

static inline int xfs_bmapi_whichfork(int bmapi_flags)
{
        if (bmapi_flags & XFS_BMAPI_COWFORK)
                return XFS_COW_FORK;
        else if (bmapi_flags & XFS_BMAPI_ATTRFORK)
                return XFS_ATTR_FORK;
        return XFS_DATA_FORK;
}

/*
 * Special values for xfs_bmbt_irec_t br_startblock field.
 */
#define DELAYSTARTBLOCK         ((xfs_fsblock_t)-1LL)
#define HOLESTARTBLOCK          ((xfs_fsblock_t)-2LL)

/*
 * Flags for xfs_bmap_add_extent*.
 */
#define BMAP_LEFT_CONTIG        (1 << 0)
#define BMAP_RIGHT_CONTIG       (1 << 1)
#define BMAP_LEFT_FILLING       (1 << 2)
#define BMAP_RIGHT_FILLING      (1 << 3)
#define BMAP_LEFT_DELAY         (1 << 4)
#define BMAP_RIGHT_DELAY        (1 << 5)
#define BMAP_LEFT_VALID         (1 << 6)
#define BMAP_RIGHT_VALID        (1 << 7)
#define BMAP_ATTRFORK           (1 << 8)
#define BMAP_COWFORK            (1 << 9)

#define XFS_BMAP_EXT_FLAGS \
        { BMAP_LEFT_CONTIG,     "LC" }, \
        { BMAP_RIGHT_CONTIG,    "RC" }, \
        { BMAP_LEFT_FILLING,    "LF" }, \
        { BMAP_RIGHT_FILLING,   "RF" }, \
        { BMAP_ATTRFORK,        "ATTR" }, \
        { BMAP_COWFORK,         "COW" }


/*
 * Return true if the extent is a real, allocated extent, or false if it is  a
 * delayed allocation, and unwritten extent or a hole.
 */
static inline bool xfs_bmap_is_real_extent(struct xfs_bmbt_irec *irec)
{
        return irec->br_state != XFS_EXT_UNWRITTEN &&
                irec->br_startblock != HOLESTARTBLOCK &&
                irec->br_startblock != DELAYSTARTBLOCK &&
                !isnullstartblock(irec->br_startblock);
}

/*
 * This macro is used to determine how many extents will be shifted
 * in one write transaction. We could require two splits,
 * an extent move on the first and an extent merge on the second,
 * So it is proper that one extent is shifted inside write transaction
 * at a time.
 */
#define XFS_BMAP_MAX_SHIFT_EXTENTS      1

enum shift_direction {
        SHIFT_LEFT = 0,
        SHIFT_RIGHT,
};

#ifdef DEBUG
void    xfs_bmap_trace_exlist(struct xfs_inode *ip, xfs_extnum_t cnt,
                int whichfork, unsigned long caller_ip);
#define XFS_BMAP_TRACE_EXLIST(ip,c,w)   \
        xfs_bmap_trace_exlist(ip,c,w, _THIS_IP_)
#else
#define XFS_BMAP_TRACE_EXLIST(ip,c,w)
#endif

void    xfs_trim_extent(struct xfs_bmbt_irec *irec, xfs_fileoff_t bno,
                xfs_filblks_t len);
void    xfs_trim_extent_eof(struct xfs_bmbt_irec *, struct xfs_inode *);
int     xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
void    xfs_bmap_local_to_extents_empty(struct xfs_inode *ip, int whichfork);
void    xfs_bmap_add_free(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
                          xfs_fsblock_t bno, xfs_filblks_t len,
                          struct xfs_owner_info *oinfo);
void    xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
int     xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
                xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
int     xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
                xfs_fileoff_t *last_block, int whichfork);
int     xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
                int whichfork);
int     xfs_bmap_one_block(struct xfs_inode *ip, int whichfork);
int     xfs_bmap_read_extents(struct xfs_trans *tp, struct xfs_inode *ip,
                int whichfork);
int     xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
                xfs_filblks_t len, struct xfs_bmbt_irec *mval,
                int *nmap, int flags);
int     xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
                xfs_fileoff_t bno, xfs_filblks_t len, int flags,
                xfs_fsblock_t *firstblock, xfs_extlen_t total,
                struct xfs_bmbt_irec *mval, int *nmap,
                struct xfs_defer_ops *dfops);
int     __xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
                xfs_fileoff_t bno, xfs_filblks_t *rlen, int flags,
                xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
                struct xfs_defer_ops *dfops);
int     xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
                xfs_fileoff_t bno, xfs_filblks_t len, int flags,
                xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
                struct xfs_defer_ops *dfops, int *done);
int     xfs_bmap_del_extent_delay(struct xfs_inode *ip, int whichfork,
                xfs_extnum_t *idx, struct xfs_bmbt_irec *got,
                struct xfs_bmbt_irec *del);
void    xfs_bmap_del_extent_cow(struct xfs_inode *ip, xfs_extnum_t *idx,
                struct xfs_bmbt_irec *got, struct xfs_bmbt_irec *del);
uint    xfs_default_attroffset(struct xfs_inode *ip);
int     xfs_bmap_shift_extents(struct xfs_trans *tp, struct xfs_inode *ip,
                xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
                int *done, xfs_fileoff_t stop_fsb, xfs_fsblock_t *firstblock,
                struct xfs_defer_ops *dfops, enum shift_direction direction,
                int num_exts);
int     xfs_bmap_split_extent(struct xfs_inode *ip, xfs_fileoff_t split_offset);
int     xfs_bmapi_reserve_delalloc(struct xfs_inode *ip, int whichfork,
                xfs_fileoff_t off, xfs_filblks_t len, xfs_filblks_t prealloc,
                struct xfs_bmbt_irec *got, xfs_extnum_t *lastx, int eof);

enum xfs_bmap_intent_type {
        XFS_BMAP_MAP = 1,
        XFS_BMAP_UNMAP,
};

struct xfs_bmap_intent {
        struct list_head                        bi_list;
        enum xfs_bmap_intent_type               bi_type;
        struct xfs_inode                        *bi_owner;
        int                                     bi_whichfork;
        struct xfs_bmbt_irec                    bi_bmap;
};

int     xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_defer_ops *dfops,
                struct xfs_inode *ip, enum xfs_bmap_intent_type type,
                int whichfork, xfs_fileoff_t startoff, xfs_fsblock_t startblock,
                xfs_filblks_t *blockcount, xfs_exntst_t state);
int     xfs_bmap_map_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
                struct xfs_inode *ip, struct xfs_bmbt_irec *imap);
int     xfs_bmap_unmap_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
                struct xfs_inode *ip, struct xfs_bmbt_irec *imap);

#endif  /* __XFS_BMAP_H__ */